Everyone gets a solo during the "AISHITERU" part EXCEPT Zukki, how sad is that? Looks like the "Daisuki" parts are duo'd, which is fine. The line distribution is fine overall. Lots of duo parts to go around.
Masaki and Mizuki got two solos since their "A (Reina) I (Riho) Shi (Mizuki) TE (Masaki) RU (Sayumi) was doubled up on the second verse so I GUESS you could they they do the subleads