I have a theater room your size. I added 4x8 wall panels from 4seating.com. I have plush carpet on the floor and nothing on the ceilings. Believe it or not it is almost to much. It is great for the theater room but not for a two channel room.
I just added cinema round panels from Vicoustic Acoustics in my very large great room where my two channel area is. My room is 25'w by 40'L with 16' ceilings. Just adding 4 2'x8' cinema round panels helped my room substantially. Vicoustic provided a whole analsis of my room after providing them a video. I have used GIK and Audiomute. With your low ceilings, I don't think you will need that much. Do it in stages....see how it sounds.
I just added cinema round panels from Vicoustic Acoustics in my very large great room where my two channel area is. My room is 25'w by 40'L with 16' ceilings. Just adding 4 2'x8' cinema round panels helped my room substantially. Vicoustic provided a whole analsis of my room after providing them a video. I have used GIK and Audiomute. With your low ceilings, I don't think you will need that much. Do it in stages....see how it sounds.