Thanks for the feedback and I'm glad you're enjoying the game and the new features!
As for your points:
1) That's a fair point, although keep in mind that the Morph spell is always an option, especially with the Copy status. Limited cure options is part of the appeal of these modes, I'd say, but it's also true that having it happen to Lilina can be an unfortunate outcome. Perhaps a method to cure Lilina specifically could be added to avoid these sorts of roadblocks.
2) I agree that some tweaking may be in order (I've had multiple people report that the Chest of Maid Outfits is notoriously difficult to find depending on your RNG), though right now the availability of key items is 1-to-1, so since there are actually 15 Mask Fragments in the City of Mist, they do take a big chunk of them just given how far they outnumber other types. As for the stadium, that sounds like a bug, so I'll be taking a look at that.
3) The Laelaps have been in need of a nerf for a while, to be honest, so you can expect that to happen in both Normal and Hard. Pretty much all of these issues ties into the AI, which is tricky given what RPGM is capable of, even with plugins like the ones I use. But I'll be tweaking them as development advances and I'll fix the Slime+Mindbreak issue right away!
4)I've had some other people report this and I'm working on a solution. It seems to be related to her necklace flashing "move."
Again, thank you for the feedback!