It's been mentioned before, but I'd really like to be able to produce albums! It's confusing to me that we can only create singles when it's albums that seem to generate the most hype/sales in the real world. I saw an idea of making them a once-yearly thing and I think that putting them on a 6 or 12 month time limit would be perfect. They could even have restrictions - Fujimoto made you release an Enka single? Well that won't fit on your Rock/Pop themed album! And maybe once a single has been released on an album it's banned from other albums so you can't just re-release the same songs over and over.
Another thing I'd really like, though it might be just me, is another ambient song or two on the building screen and the concert screen - I've been playing this game a lot since my friend showed it to me, but I'm really getting sick of hearing the in-game music over and over and over again (and yes, I know I can mute it, but...). If there were another couple of songs so that there was variation in the loops I think it could be really cool - they could even reflect the kind of music that your idols are most proficient/prolific with! (though that could get tricky with multiple groups etc). It just feels like in a game about creating music that there could be a little more actual musical option? Even if the same basic loop is just tinged with slightly different options to represent the musical styles in game? Sorry, I'm not a musician, but like, taking the loop that exists now and just playing it in a electric guitar for a metal theme, or making it a bit 'bouncier' for a pop theme... etc, etc.
Anyway I've been really loving this game and I can't wait for the full release ♥