And a lot of room for new indoor tilesets interests me and sounds amazing. Now I'm really wishing I didn't have to leave for work now. I just want to try this stuff out, haha.
As for the indoor primary tileset, I'm thinking of porting a lot of FR/LG indoor tiles, along with their respective palettes, to the empty tileset. If I ever do get around to it (which is highly unlikely), I'll probably post a patch in the ROM Hacking Resources thread.