So tell me if im cooking or not, but im thinking about my DanganAllNight AU again. I like to think that Sayaka would use her idol background to train some of her classmates a step further than basic dances and singing. I think she'd go intensive with the training considering they're put in a life or death situation here, but yhea I'd imagine her making an idol bootcamp.
And who's enrolled in Idol Bootcamp? I think Sayaka would handpick the classmates she thinks would do the best at the job in the sense that they would take easiest to rigorous training, also I think its funny. The candidates I think she would pick out? Asahina, Mukuro/Junko, Sakura, and Kiyotaka.
They wouldn't be like actual idols, Sayaka would just need them to do the dancing and singing so Aoi would be perfect, in her eyes, pretty and already does regular training. If Sayaka only knew Mukuro as Junko (havent thought about it to hard) then Id also imagine she'd have a similar thought process to picking Aoi, pretty face, pretty body, and a fashion model should be used to having to take orders and stuff.
The fun ones I think would be Sakura and Kiyotaka. I think she'd pick Sakura probably off of Asahina's suggestion and then Sayaka would think about and totally dig it. I mean Sakura might not be built the way an average Idol looks, but she has strict training and takes care of her fitness extremely well, so it would be a natural shift to adopt Sayaka's extra-indepth idol dancing daily practice sessions. Kiyotaka probably keeps himself exercising regularly as well, but more importantly he's very effort focused, he puts 110% effort into everything so Sayaka would naturally see that and decide that if she tried to train him into an idol, he would put in a staggering amount of effort into doing a good job.
Aside from that, I just think its entertaining to think of them as an idol group. Mukuro having to mask even more and take her impersonation of Junko to new limits, her military training kicking in when she's put into super idol training. Sakura being this like giant idol girl who honestly kinda loves the whole thing, but may feel self conscious about it. Asahina fits in pretty well, and honestly shes saved by the fact it would be mostly singing and dancing and none of the public appearance stuff because she wouldnt be able to hide her real emotions at all. Kiyotaka being the one boy of the group and also being extremely awkward as a person, but extremely dedicated to doing stellar at this task he's been given. Probably the stiffest of them all in the beginning.