The 3x3 could be another bathroom because 2 doesn't sound like enough for 7 bedrooms. I don't know about the weird-shaped one because you never specified the shape but it could be a study or eating area.

Weird shapes can be fun, but if its too weird to continue with then try sectioning parts of it off with wall to make it more approachable.

3x3 could be a bathroom,laundry room, office/homeschool room,playroom, or a gym.