I personally thought UFO Normal didn't seem ridiculous (SA normal, definitely is the hardest to me). I thought it was fine for a Normal. If you're not used to the UFO system already though, then, well, yeah, that'd make a big difference.
UFO's difficulty skyrockets in the change to Hard, though. It's seriously more difficult to me then many of the other game's Lunatics. Getting the MarisaB 1cc was quite a fun challenge. This makes me sorta sad, that the difficulty is so incredibly high; UFO would be my favorite game otherwise. Fun and varied balanced shottypes (With MarisaB for Challenge Mode), lovely interface and menu theme, good music and lovely patterns in general, a ufo system that adds extra depth beyond just "DODGE BULLAT". But then everything goes down to bombing the eff out of next to all attacks instead of actually dodging them, or else DIE HORRIBLY.
I mean, Ten Desires isn't -anywhere- near as appealing. It's just sort of "eh" to me. A ton of the patterns and stages are just... eh. It's not very captivating. It has low difficulty, but I don't even like it enough to feel like trying to 1cc lunatic, which from what I hear is also not that hard. It doesn't help that I've been holding back until the English Patch is out so I can read the endings, though...
Maybe I should try UFO Lunatic again. It's been an awfully long time... as I said, over a year! I'll probably remember why I gave up though, after I try.
...why does my favorite UFO shottype have to be MarisaB? :c It's a dumb Forward-Focus shottype with no power, that pretends to be spread! (That spread barely even takes out popcorn fairies running across the screen at max power before they reach your base shot, don't you lie to me.) Although I guess I haven't played UFO in like a year, anyway. And yes, it was still the last shottype I 1cced Hard with, I'm not crazy!