Some people use direct radiating in the rears for music reasons. However, for HT use the Q's will still perform better. Actually, I think my 4 Q's do great for music as well, pretty much wraps you in the sound.
I'm also not a fan of "in-ceiling" speakers for left/right surrounds or rears. It basically goes against the whole purpose of how those channels are to be experienced.
I would try to ceiling mount some Q's either with a DIY method or Axiom bracket. They will not block the windows that much and if you get the right color to match your room decor, they will compliment your room.