I mostly agree with what people said about LoT1 vs LoT2, here, but there's one thing I heavily disagree with - character balance
LoT1's characters were a LOT less balanced between each other than LoT2. There were a lot of characters which were simply outclassed in nearly every possible way. In LoT2, you have 2 more elements, skills which enables chars to do absolutely unique things (like Cirno's unresistible SPD debuffs, or Reisen's Intense Vertigo, or Maribel's "treat enemy buffs as debuffs", and so on). In LoT1, chars basically had only 4 things they could do: deal damage, heal, tank, or buff. Sometimes status/debuff. That's it. And there was a lot of overlap between the chars, with some getting the short end of the stick in a pretty ugly way.
In fact, if I were to classify LoT1's characters based on lategame performance (something I intended to post a while ago here, after having defeated WINNER 256 times but never did), I'd probably file them as follows:
RANK S (These characters should be an automatic entry on any competitive team - any team not including these chars is almost automatically worse as a result):
Reimu: By far the best healer in the game. Impressively balanced stats mean that she can easily stay on the frontline while supporting her team, and the overall generous multipliers of her spellcards allows her to deal consistent damage for a healer/support character. Evil Sealing Circle provides paralysis support, while Great Hakurei Barrier helps buffing the team's defenses. Reimu is possibly the best character in the game overall, and whether she lives or dies generally makes the difference between winning or losing battles.
Nitori: By far the best nuke in the game, and it's non-elemental to boot. Only Flandre, Yuuka, and Marisa can outdamage her on a single blow, but their horrid drawbacks don't allow any of them from spamming their attacks like Nitori can. Optical Camouflage counteracts the low delay of her Megawatt Gun. Her bulk isn't great, but still okay for the best damage dealer in the game.
Rinnosuke: The MANnosuke is an impressively well-rounded char. World Shaking Military Rule is a great opening move against nearly every boss, and Rinnosuke's high speed often allows him to act before his allies. Shining Stars of Traumerei can deal as much damage as the likes of Youmu or Yuugi, while Start of Heavenly Demise is a good backup non-elemental option. What defines Kourin, however, is his ability to act both as a real nuke AND a real tank, while boasting what possibly is the best opening in the game. He might technically be master of none (he doesn't hit as hard as Nitori, nor does he tank as well as Keine), but his combination of feats actually makes him a master in a way no other char in the game can possibly emulate.
Keine: If Reimu is the best healer, and Nitori is the best nuker, Keine is arguably the best tank in the game. No, she's not as self-sufficient as Meiling, but she has incredibly powerful buffing options for keeping your entire frontline fully loaded. And, as if this wasn't enough, she has defensive stats that (when taking levelling rates into account) eclipse every other tank in the game except Meiling herself - while still boasting a surprisingly decent speed stat. Tanks are defined by their ability to balance bulkiness (being able to take the boss's attacks) with efficiency (making good use of all those turns they get), and no char gets that balance as well as Keine does.
Shikieiki: Shikieki's Last Judgment is simply amazing. Not only it hits about as hard as Youmu's Slash of Eternity (and noticeably harder than Yuugi or Suika), but it is fully defense-piercing AND non-elemental. By virtue of this alone, Shikieiki is the only char on the entire team who can ALWAYS deal solid damage on bosses, no matter what. This is why every competitive team should have a slot for her.
RANK A (These characters excel at what they do in such a way that they're an easy fit on any possible team. They have very few flaws, if at all):
Youmu: Has the 3rd strongest, drawback-less nuke in the game after Nitori and Suwako (and, unlike Suwako's, her nuke is non-elemental), coupled with excellent HP and defense which allows her to stay in the tank spot comfortably when needed.
Yuugi: One of the best single-target nukes in the game (though not as strong as Youmu, Nitori, or Shikieiki), along with high HP and Def which allows her to tank if needed. Has a less powerful, but still good option for non-elemental damage. Irremovable Shackles can cause PAR and PSN, but unlike some other PAR-inducing moves its damage output is terrible.
Ran: One of the best tanks you can choose from. Her AoE buffs are a bit on the slow side, but can buff even the backlines, making her a great choice for tanking bosses in the first few turns. Her bulk isn't amazing for a tank, but still more than enough with HP investment.
Flandre: Lavatein is great for farming purposes, while Starbow Break does solid damage to bosses, is non-elemental, and has a very fast delay for an attack hitting almost as hard as Yuugi's Knockout in Three Steps. Despite SB's recoil, Flandre's high HP allows her to stay on front and keep attacking, but she's heavily reliant on Reimu to be effective - no other healer can realistically keep her up as well as the rest of the front line. That being said, Reimu is a char you'd want to use anyway, so don't let it deter you from trying Flandre either.
Yuyuko: By far the strongest mage in the game. Her stats are nothing to write home about, but Saigyouji Flawless Nirvana is simply amazing, with a crazy multiplier and a surprisingly low delay for such a nuke, making Yuyuko's "actual" speed almost on par with the likes of Nitori. And while her physical bulk is average, her magical bulk is great too, allowing her to tank MAG attacks better than the likes of Youmu or Yuugi even when factoring HP.
Mystia: Possibly one of the most underrated characters in the game. Her stats may appear mediocre, but her excellent levelling rate goes a long way balancing them out. For a low-delay attack, Ill-Starred Dive is incredibly powerful (especially if compared to something like Cat's Walk or Flight of Idaten). But Mystia's real claim of fame is her Midnight Chorus Master. Not only it hits as hard as you'd expect a good nuke to (and is non-elemental to boot), but also comes with a PAR chance attached, allowing Mystia to suddenly turn the tables on nearly any opponent with a little luck.
RANK B (These characters are very good at what they do, but have some shortcomings which might hamper their usage. They can still be accomodated on even the most competitive of teams, but they require some care in the team lineup or their usage):
Minoriko: Possibly the best healer after Reimu. Wish for Abudant Harvest may be single-target, but its short delay allow Minoriko to keep multiple chars topped in a way other single-target healers cannot. Falling Leaves of Madness deals chip but useful and fast damage, while Promise to the Wheat God keeps tanks buffed. Minoriko's bulk is kinda mediocre, but her levelling rate and excellent healing skills make up for it somewhat. Still, more of a backup to Reimu than anything.
Rumia: The only other real AoE healer besides Reimu. Sadly, even with solid investment, Demarcation rarely heals more than 30-35% of the HP of a nuker, and is absolutely incapable of keeping tanks topped in the same way Reimu or Minoriko can. On the plus side, however, Moonlight Ray actually allows Rumia to dish out solid damage for a healer, though she won't get many opportunities to do so due to her need to constantly spam Demarcation to keep up with most bosses.
Komachi: Impressive bulk thanks to her HP score, and surprising (but not actually excellent) single-target damage output with Scythe that Chooses the Dead. Good choice if you want a tank who can actually deal damage (and do some minor status support if needed), though there're probably better options for damage dealing.
Suwako: Strongest drawback-less nuke in the game after Nitori. Unfortunately, held back by subpar bulk. However, if you can keep her alive, she's easily one of the best nukes in the game - though it should be noted that, unlike many other nukers, her nuke is not non-elemental.
Suika: Similar to Yuugi in many respects - same multiplier on her nuke, same HP growth. Unfortunately, the differences - slower levelling rate (compounded by slightly lower ATK), lack of non-elemental backup attack - can't be ignored. While Suika can work as a nuke (and her Missing Power buff becomes slightly more effective the less Speed counts at higher levels), she still is a fair bit worse than Yuugi and other major nukes.
Kaguya: Hourai Barrage hits very hard, and ignores defenses to boot (though, unlike Eiki's Last Judgment, is not non-elemental). Buddha's Stone Bowl also can help if you need an emergency second heal from Reimu. Unfortunately, all this is set back by an awful physical bulk, even worse than Suwako's, which makes keeping Kaguya's alive against the likes of WINNER a chore (and a magical bulk which is still significantly worse than Yuyuko's). Kaguya is not unusable, and the reward for doing so is significant, but the risk factor is too big to ignore.
Yukari: Great defenses for a tank, a good defensive AoE buff, and a great support option in Yukari's Spiriting Away. Unfortunately, however, the way Speed scales in the game weakens its effectiveness, especially compared to actual offensive buffing. Still a good option for tanking, especially at lower levels.
Renko: Another good, purely-supportive tank. Sadly, even at high speeds, the delay cutting effect of Charge is too large of a flaw to ignore, but its ability to instantly top the buff levels of the entire frontline shouldn't be underestimate - and when she's not busy buffing, Galaxy Stop is a good way to fish for a PAR chance.
Maribel: Her stats may not look impressive, but Overflowing Unnatural Power is so good that she actually can be usable. Not the strongest damage dealer in the game, but even at high levels, her superior speed and low delay allow her to deal overall as much damage as a medium-power nuke like Yuugi or Suika. Furthermore, her debuffs may be weak, but she gets multiple opportunity to apply them and stack them to decent levels.
Kanako: Unlike other middling, bulky mages, Kanako actually has a real nuke in Beautiful Spring Like Suiga. While she won't do as much damage as the likes of Yuyuko, this is somewhat countered by her excellent bulk, which allows her to stay out comfortably in a way few other similarly offensive chars can imitate. That being said, she's no Rinnosuke - while her combination of bulk and offensive potential is interesting, she doesn't really shine at neither, and doesn't have anything other than damage to bring to the table (furthermore, her non-elemental option is very mediocre).
Yuuka: Master Spark is great for farming purposes - and unlike Marisa, she's not limited to single-target encounters. She's also far bulkier than the other Master Spark user, and more than capable of staying on the frontlines. Unfortunately, Flower Shot's damage output is kinda pathetic even when factoring her low delay, meaning that she can't work as well as Flandre on boss fights (though, at least, she's less dependant on heals to do so).
RANK C (These characters are not completely outclassed, but it's hard to justify their inclusion on a team because what they are capable of isn't particularly useful):
Marisa: Master Spark is useful for farming most 30F encounters (except those involving multiple enemies like Eientei), and no character can muster as much damage as Marisa in a single blow. However, her horrible bulk, combined with Master Spark wiping her SP whenever she uses it (and her other spellcards having awful multipliers) means Marisa is of little to no use in prolonged battles like WINNER.
Sakuya: Lunar Dial is just about all she has going for her, but speed buffing becomes progressively less powerful as your level increases. Her damage output is pitiful, and she has no other relevant options to bring to the table.
Meiling: She can tank hits, but she can do literally nothing else well. Healer is almost useless once every char has status immunity in the late-game. Mountain Breaker has good piercing factor but bad ATK multiplier, which is not helped by her mediocre ATK value. Colorful Rain is good, but again, this only helps her tanking hits, and there're plenty of chars who can actually support their team (or doing relevant damage) while doing so.
Cirno: Can debuff speed faster than any other char, but useless otherwise. Bad bulk, bad damage output, and there are tons of better characters who can deliver paralysis.
Aya: Pretty much in the same boat as Sakuya. Good if you need SPD buffs, but SPD buffs are not as good in the lategame, and that's all Aya can really do compared to other chars.
Iku: One of the best single-target offensive buffs in the game. However, still pales in comparison to the likes of Keine, who can keep up an entire frontline buffed. Furthermore, Iku's damage output is mediocre, and her bulk is good but not outstanding.
Sanae: Yasaka's Divine Wind is a powerful heal, but unfortunately its high delay means Sanae has a hard time solo-healing the front line against hard-hitting bosses. Miracle Fruit is a decent single-target buff, but, again, there are better options for buffing as well. Her bulk is mediocre, and her damage output even more so.
Reisen: Her damage output is mediocre, even with Grand Patriot's Elixir - meaning that, if you use her, you're basically using her for Discarder's debuff. Even so, Maribel is probably a better option, unless you really need your debuffs to hit reliably.
Eirin: Hourai Elixir's %-based heal, overhealing, and high delay means that Eirin, like Sanae, is good at keeping up tanks but can't support a front line on her own. Astronomical Entombing does decent damage for a healer, though.
Tenshi: Her bulk is quite average despite her high defensive stats, and her damage output is just sad. Useful for removing debuffs, but can't do so reliably enough to easily justify a team slot.
Rin: A bit better than Cirno, in that Blazing Wheel can actually deal good damage, but still a bad choice for similar reasons - bad bulk, less use for fast switchers in the late-game, lack of other relevant options.
Utsuho: Her only perk, over other similar good mages with bad spellcards, is Giga Flare's piercing effect. Besides that, though, there's little Utsuho does that can't be accomplished by other, stronger characters.
RANK D (These chars are almost strictly outclassed in every relevant way; they should basically never be a serious consideration for any competitive team):
Remilia: Spear the Gugnir's multiplier is absolutely horrible, and she has nothing else to boast about. Buff support is easy enough to come by that Curse of Vlad Tepes hardly counts (and, even so, there are better self-buffing characters too). As a tank, there are way better choices - whether you want a damaging tank or a supporting tank.
Patchouli: Horrid bulk means she has a hard time taking blows from nearly anything. Her damage output is mediocre, due to the low multipliers of her spellcards. If you really want to use a slow magic attacker, both Kaguya and Yuyuko are far better alternatives.
Chen: Awful bulk which undermines what she's better at - switching chars around fast. As levels and Speed values increase, this niche becomes less useful too. Mystia can do the same thing better in almost everyway. Low spellcard multipliers and mediocre Atk (despite levelling rate) negate any attempt to use Chen efficiently as a damage dealer
Alice: Decent stats, but subpar damage formulas. Not as bad as Patchouli, but still cleanly outclassed by more powerful mages.
Wriggle: If you really want a char who can use Poison, use Yuugi or Shikieiki. Not much else to say about.
Mokou: Another mage with decent stats, but mediocre spellcards multipliers. Not much else to say.
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I'm not sure if a similar ranking could be done for LoT2 chars, even once we get to see the end-game, due to how more synergy-dependant they are (whereas LoT1 chars were much more easily gaugeable on their own). But, if I used the same criteria as above, I doubt I'd end up putting any char in Rank D or S, in the end. Sure, there are some chars which are better than others, but I can't think of a single char who's truly outclassed at EVERYTHING - nor can I think of a char who's so good that she should be an automatic entry on any team (even Nitori slowly loses gas as levels raise, and I wouldn't rule out the possibility that, in the long run, a team with well chosen kin synergies could end up slotting her out with no regrets).