I’d like to see a show where every the origins of every character’s moe facets are explored and shown on screen.
You would get to see the entire childhood friendship from day one to day they’re no longer kids. You’d get to see the exact environment that would turn someone tsun and dere. It wouldn’t just be a part of their personality from day one.
Basically, I think, the result would be that you get to see more of the characters’ parents, which is perhaps not something that happens often in this sort of anime.