What are you gonna use her for?
Mamiya is so strange to me. Great awakenings, great skill despite needing flampy, but her stats are pretty shoddy even at hypermax.
Scarlet Descended when I plan to Shiva Dragon farm her. I just need 1 or 2 Ares to complete the team.
Very good for dungeons with pre-emptive jammer spam (I ran Mamiya when I was speedfarming Batman Collab 2 Gotham to one-turn kill Joker, for example) also if I run Shiva Dragon
She's a solid niche sub IMO, very legit, and thanks to the 4 Dark Resists it allows me to tank a lot of fuck-off attacks I normally wouldn't be able to.
EDIT: Also my Mamiya isn't LV99 yet. The stats won't be much better at hypermax but I feel they need to be hypermax for her to be even worth using on harder descends.