Hmm...I've become overleveled for everything because I had to be to stand a chance before, but now with a full party, I have to leave people behind to drive my average below the challenge level. For the stuff. I need the stuff.
Team ⑨ is great at sweeping trash, but isn't as effective in bosses, simply because Wriggle's the only one who can take a hit. They are crazy fast, though.
is also great at trash sweeping. A quick Soul Sculpture wipes out most enemies. The ones it doesn't...well, that's what Extra Attack is for.
They are bulky enough to stay out in bosses, too. Except
. You look at her funny, even magically, and she goes down.
Malice is...well, Marisa gets to be kinda disappointing after the first quarter of the game. I'd be lying if I said she was useless, though, because Master Spark. Alice, however, is awesome, and turns into an unstoppable killing/sweeping/debuffing machine with Marisa out.
xKeine is the least impressive of the groups I'm working with.
certainly turns into a pretty good tank with Keine out, but she was already a good tank to start with because of Resurrection, so it's redundant, and the boost Keine gets isn't noticeable because I mostly just use her to buff. And her attack spells aren't great to start with. Good at the beginning, but lose effectiveness fast.
Edit:
Due to the nature of this battle, I think your well within the limitations to throw out Lv1s.