I wouldn't say Byakuren is broken. Strong, yes. Broken is Nitori. Her abilities to give buff to people are superb, but as far as damage is concerned, it isn't that high. She's just a really good offensive support buffer thing.
And I just realized Nazrin has a passive that allows her to copy Byakuren's current buffs. Time for Nazrin-Byakuren shenanigans?
Maybe not completely, but I'm pretty sure Byakuren completely outstrips every other buff-based character in the game except
maybe Ran. Once she has all the stat amps she pretty much straight up obsoletes Sanae and all the multi-target buffers (Ran, Keine, Iku) don't exactly sit around keeping themselves at 60%+ on all stats naturally, have far more MP problems, etc. I think the only drawback is that she is hella skill point reliant but you get her so late that you can get the majority of valuable allocations immediately; and to be fair, Nitori's in a similar boat where she doesn't start obsoleting the rest of her class until Maintenance can really start to kick in as well.
Point is I almost want to switch back to Sanae because, much like Nitori, it almost feels too easy to use Byakuren right now. ...But, she helps everyone else do their shit really well and lets everyone
else shine so I don't mind it as much.
For the record, my party approaching the end of the game: Momiji, Yuugi, Sakuya, Reisen, Komachi, Wriggle, Reimu, Byakuren, Cirno, Parsee, Patchouli, Yuka. When I stream the game tonight from work I'm going to be fighting Eiki (my last recruitment; I had to farm for achievements) and then exploring the 19th floor. ADVENTURE HO~
Oh and yeah Nazrin just sorta passively borrowing all Byakuren's buffs probably makes her super silly if not for the fact I doubt Byakuren has any problem with having the turns to manually buff Nazrin anyway, but hell yeah tiny tiny buffed-as-hell commander.