I'm considering using the 'throne room' for a male and then filling the rest with a sorority and community. Only considering the sorority right now, but since the water in the tanks don't mix that means the throne room is safe from current and diseases but will be kept at an even temp with the rest of the tank. It'd be easy enough to give the male hiding places away from the 'community' and vice versa. Lol, told my boyfriend that in a few months he'll be eating breakfast with a big fishtank on the table xD
But I think it's a fantastic idea and I'm excited to plan everything for it =) I already have a halfmoon 3 gallon with a clear lid that I like, so I think another would work just fine as the 'throne room' (that is such a perfect name btw). I think the halfmoon design really gives the betta maximum entertainment and 'socializing' as well as a view to the outside world if he so likes. Also takes up a little less room so your community can get around it easilly instead of it partially partitioning your tank like a rectangular tank might.
I thought about a cylindrical 2 gallon I also have, but figured a cyllinder within a tank would make seeing the betta super hard and expose him to the community all day save for the cave's and plants he'll have in his own space.
Altogether I'm sooo excited to start planning this project =D