I really dig the room. The Daleks, 'VICTORY' pic is cool.
However, there are too many angles, and with the glass windows right behind you, I am sure there are tons of reflections bouncing around the room.
Before you go down the sound absorption rabbit hole. Identify exactly what you want to do....Too much bass, dialog not clear, etc...
With as many corners as there are, corner diffusers would add $ up quick. Also, those windows, with a great view, will cause all sorts of reflection/refraction issues.
Identify the problem, then look for a solution. However, if the sound worx from the MLP, then what are you looking for, specifically?