lv57, 4706 MAG, 46 skill levels in MAG
You said you did no grinding right? If you're 57 with Marisa in 15F, It just confirms that being 60 with Reimu for the BOSS of 16F is probably a mistake in numbers.
Anyway I'm like 2/3 done 16F atm and my Marisa is 69 with 45 levels in MAG (I focus on it more when she becomes nothing more than a spark-spammer, but for now she's still more useful for other stuff) and 5500 magic.
Anyway Marisa is useful for 15F with the following IMO:
Sorceresses: These are chumps anyway who cares
Knights: She's especially poor against them because of their high mys resist
Tengu: She's pretty useful for these because she's one of the few characters capable of outspeeding them if you have a decent level and you don't neglect speed. She wont solo them, but combine her with another fast aoe nuker (who doesn't use wnd or spi elements) and you got them under control
Spectre: Oh god she sucks.
Dorf: Nothing special. Slower nukers probably fare better though, they don't really have any outstanding weaknesses or strengths.
Blackenmel: Marisa is very useful for these. You may dish out 0 damage with her against them when you first enter the floor, but before long asteroid belt and 2 or 1 shot them. Asteroid belt only, it has a better mnd piercing effect than magic missle and earthlight ray. If you're desperace you can concentrate before unleashing a asteroid belt, in which case it should definately 1shot them.
Crystal head: These are like dorfs pretty much. Basically you HAVE to use magic only, not physical, they are weaker to cold than any other element, but cold generally isn't very available, so Marisa is pretty average here.
so basically Marisa is great for the tengu and blackenmels, which are probably the biggest threats in the floor, and she's average for everything else but knights and spectres, knights she's poor at and spectres she's near-useless against.
She's great against the easiest miniboss on the floor hill gigas btw.
