I'm currently near the end of the epilogue and fights are getting harder. Was wondering who should I swap gran and IO for, or keep gran but swap out IO for (ai seems really bad with her). I was thinking of at least getting Cag or/and Vane but not sure which or both and what skills to equip them with.

Controlling Zeta: What 4 skills should I be using?

AI Rosetta is using spiral rose/bouqet/rose tycoon/lost love

AI Gran is using Rain of Arrow, phalanx, panacea, stall. Not sure if phalanx is helpful cuz I still get one shotted sometimes (how bad is she at using that buff?)

AI IO has minimal investment and needs to be swapped out for someone else.