My head has been spinning over the last week about different speakers and speaker location. I need some advice. I am by no means a genius with these things.First I have a 15' D x 20' W family room being built in my basement. I am planning on doing 5 speakers and a sub. I am thinking of doing 1 center ( Monoprice #6317 ) under my 60"TV on the 2'x5' fireplace bumpout on the front wall. I was thinking of getting a pair of Monoprice #6816's to mount in my wall. The speaker wall placement would be to the left and right of the sectional, approximately 18" in front of the sitting area and 5' to the left and to the right of the sitting area. Also getting a pair of Monoprice #4929 to mount in the ceiling directly behind the sectional 18". I would also get the 12" sub and pair it all with a Yamaha 477 receiver.Question #1 , is Monoprice quality and sound? I will watch more sports and movies in that room. I was looking at Polk audio or Pyle speakers also?. #2 Speaker placement? I can not put in wall speakers to the left and right of the TV due to windows on each side of the bumpout. Also can not put a center speaker above the center of the TV in the ceiling due to a floor truss. Should I get another pair of ceiling speakers for my fronts and upgrade to a 7 channel receiver? #3 Mixing in wall and in ceiling? Dumb or Ok? Maybe do all ceiling or keep it mixed? #4 I am doing blown insulation in my ceiling for sound and foam insulation in my exterior walls? Do I need to build a box for the speakers for protection? If so, what do I make it out of and how much clearance do I need on the back of the speaker to the box?Thank you all