The Dearly Stars characters need their own anime, not just a twelve episode one though, which is probably what would happen if they ever did get one... 
If they were to get one, new songs would have to be written, probably. We'd also hear songs from Yumeko and possibly Mai and Reiko from their idol days, which wouldn't be that bad at all.
I keep seeing the end of the season with Ryo revealing he's a boy, but with him still disguising himself as a girl in ep. 10 of anim@s, I believe, that wouldn't happen.
And the girls were working on solo careers instead of together, so I think the episodes would be focused on one character at a time.
