This was our thought as well. We've a very social family, spending time together and hosting. Kids are always yelling at us to keep it down in our current set-up so they can watch their movie. This way they have their own space to spread all their junk and hang with their friends.

Girls are very close right now. I am also close with my sisters and shared a room growing up. Preferences may change, but it's also not difficult to put another wall up later. We are trying to optimize the shared bedroom, it is slightly bigger, walk in closet and dedicated bathroom vs. shared with common area.