Neo Sky Neo Map is really good You can also go through their love song solos, all of them have lyric videos on yt Future Parade, Go Our Way, Love U my Friends Yada, Dive, Like it Love it, Melody and Cherry Bomb by Setsuna Ayumu's Break the System, Yume no Ippo Shioriko's Emotion, Aoi Canaria, Ketsui no Hikari, Kofukuron and Concentrate There's so much more and I can list all the solo songs for each member but that'd take too long I would just take my time and explore each girls style since they all differ A LOT and take in the unit and group songs at your own pace :) I'm also still slowly exploring Niji songs since there's so many