Theoretically the infinite corridor IS supposed to be in this trial version, though? Maybe we misread something because google translate, but... yeah, try checking out 21f (assuming you've done b4f)
I was thinking more about the incredibly high DEF/MND buff than the heal, since only Tenshi has a better DEF/MND buff, and Tenshi's is a self buff with a crapload of issues compared to Mino's. Just having the ability to buff anyone to almost that level of defense and mind is kinda nuts.
Still, I can easily see why you would see it as a waste, as MP flow like that would be able to pay for any MP cost from the subclass spells, and her speed is just enough to make full use of them, too.
On a related note, I had been curious as to why the Enhancer and Hexer subclasses do not have a spell that buffs/debuffs speed. Would that by itself make them OP or something?
I did account for that in saying the party already has a lot of buffing power- granted that was only a glancing mention. But yeah, between people like Byakuren/Renko/Keine/Reimu/etc, for mooost of the battle apart from the very start your party should be in a state of decaying buffs, not unbuffed. 57% should easily be enough to either max it out or get them close enough it doesn't matter. Now, 89~97% buffs IS somewhat exciting for people just being switched in, but in the end, it really isn't special enough due to Minoriko's lack of other innate support (and the fact that you still need them buffed by the others for speed and/or offense anyway). Infinitely casting herbalist skills with only a rare need to concentrate is special; Desire to Rest and Rapid Charge will have her almost never needing to use a turn recouping, and Placebo lets her viably take the place of the other buffers in the front row for awhile.
On speed, it wouldn't make them OP at all imo (almost all bosses heavily resist speed debuffs before long, anyway), but speed does tend to be the more special one of the lot. In LoT1 a lot of buff/debuffs that covered "all" didn't do speed, but in LoT2 that was changed to where almost all of them do.
Mmm, only tangentially related, but Tenshi really doesn't seem that special of a tank in this game... her support passives are Keystone Formation and phys damage reduction, and whilst phys damage down is one of the better damage reduction passives, she's soooo slow when it comes to Keystone or subclass support, her only innate support skill is a self-only def/mnd buff (GRANTED, removing buffs is really useful on -some- bosses; it's just useless on most others...) and her defenses REALLY aren't much higher than anyone else's in this game, along with being forced to invest into her max hp. Level rate/library isn't notably good to help with either of those. Plus her corridor skills are mostly only good in randoms. Hooray, starts the battle with a def/mnd buff...?
She's a great bulky attacker if you use her with Iku, though, as her move formulas are actually pretty great (Plus Iku is awesome and would like her own huge def/mnd buff with tenshi out) and with base stat tweaks in Plus Disk she can actually really get somewhere with that. +40% base attack with Iku out becomes even more special when you've tweaked the base up; it's like having a 40% more powerful Attack Boost skill, attack gems etc. Granted, she needs that extra oomph to continue to be genuinely worth a party slot.
I mean, Tenshi works enough as a tank, but a lot of people are arguably tankier than Tenshi is, whilst bringing more useful support options to the table. In LoT2 before long you're choosing tanks more for their passives/skills than their stats and she hardly even wins out in stats to start with. When I've got Renko/Byakuren/Hina/Rinnosuke(switch power!! keine after corridor) as tanks with awesome support prowess that I NEED to have them out for regularly, and 3 of those are nearly-as or more tanky than Tenshi, well... Tenshi would hardly ever be out even if she was in the party :V This is also why Momiji tank loses despite having amazing stats and some alright passives, but she's also a super solid bulky attacker once you sub her for more attack moves.