Just keep farming Hh for fragments to craft crit damage drives when that come out. Stock up on EC and antis for when lunar fall comes 1 year later XD
Anyway, CHii advancement is really nice. Her advancement story IMO is one of the better ones out of the 7 characters. It also fleshed her out A LOT. I found her to be very one dimensional as a character before but her advancement really gave her some depth. I used to not like Chii becuase she felt very bland and poorly written but the advancement quest kind of salvaged her.