+ The auction restock their demons if you enter and exit Free Battle. Useful if you want to bid on more demons and/or the other bidders got what you want before you. I generally bid on what I want, enter Free Battle, grind for some extra Macca, and go back to the auction.

+/- Without spoiling anything, some characters come and go into your party, so it's better to be flexible and ready to change your skills around to fit whoever's with you right now. Obviously, you can use demons to cover up weaknesses.

I think the AI seem smarter, since I have enemies use Dia/Diarama/Amrita/Glamour/Devotion/you get the idea on themselves.