We are considering switching rooms, too. We are only in 1200sf, but only have 2 "real" br's and then the garage was converted to a larger br about 8 years ago and it is currently our office/schoolroom/internal storage (we have no outside storage). The "real" br's are small, though, only about 11x12. The converted room is a bit larger, obviously. But it's on the opposite side of the house from the 2 br's (which isn't hugely far considering it's only a living room in between, but it's a lot of space in my head!) . I can't fathom having my kids on the opposite side of the house from me, so I don't really want to move myself OR the kids there. But we are so squished in our tiny bedroom now, and all 3 kids and ALL their clothes and toys are in the other tiny room. It works fine, but sometimes I just crave a tiny bit more space....just wish the bigger bedroom were near the smaller ones.
Oh, and the bathroom is right by the smaller rooms, so it's not near the bigger one. We only have 1 bathroom.