Dark Grey convuluted foam

I would not use any type of foam product...they suckout to much energy and life and dynamics

Absorption foams when used placed at optimum locations in the room will not kill dynamics but solve 1st order reflections. Benefits include less piercing highs and a more accurate and pin-point sound. Only when you use too much of those foams placed all over the place then you would lose dynamics and life.

Too many products around. If you're looking for foams, try foambymail on the cheap. If you cannot live with the aesthetics(including myself), frame them up and cover them with acoustically transparent fabric. I bet the sound improvements will be huge compared to other tweaks as the room is one of the most important component besides the equipment and placement of speakers. With the quality of your gears I believe it is worthwhile to spend more time and effort on improving the room acoustics (especially if it's a dedicated room).

If you have side walls, try absorption on the two walls in between the speakers and your listening chair. You can either use absorption or diffusion for your front and rear wall. The TV at the middle is certainly not doing any good.

Others may have different opinons or suggestions.

I am no expert but have gone through quite a few trial and errors. It depends on what you're looking for and every room is diferent. If you feel the highs are piercing or the sound becomes 'messy' when you crank up the volume too high then you would need absorption on at least one wall. I personally ended up with absorption at two side walls and RPG diffusors at the rear. I cannot treat the front wall as I have a screen there but have tried diffusors with positive results.

If you do not plan to have treatments on the side wall then I would think you can have absorption at the back and possibly minimal absorption at the front behind the speakers. You need to try it out yourself.

On a separate matter, I find bass traps to have a positive effect in my room as well although some may not find them doing any good in controlling the bass.

You can be amazed at how well your system will perform or react in a well-treated room. Prior to treating my room I always cannot turn up the volume too high although I like my music loud or I would end up with painful ears. Now I often listen at higher volume levels without hurting my ears. It just feels great when you can just keep turning up the volume without getting a 'messed-up' sound. At that point of time you would appreciate the importance of room acoustics and maybe spend more time working on improving it.