Jason, as you pointed out in the beginning of this discussion: You have a hard bouncy box of a room and I strongly suggest that you put carpet in the room to soften things up. With such a small room, you can find carpet remnants very cheap, with a wide choice of material and colors. You might also, find an area rug that you just have to lay down. Either choice might save a lot of money. Gluing cork squares on the ceiling is another possibility, and I would do both.
Good luck
Good luck