[basementjack]

I'm going to go out on a limb here and suggest that you might not need bass trapping in that room.

Bass is often a problem in square and rectangular shaped rooms.

Your room has so many openings into other spaces, and so much furniture, that I bet it sounds VERY good right now. In fact if you measured it with some software like REW, I would not be surprised if your bass response is much flatter than what the average person has.

Maybe you've seen those 'skyline diffusors' before they have adjacent blocks of various depths and they work by scattering the sound coming back into the room - the sound hitting the tallest blocks reflects sooner than the sounds off the shortest blocks, cancelling the freqency who's wavelength = 2x the distance of the difference between blocks.

well those syline diffusors only work down to 300-500 hz due to the size of the blocks - your room however has openings much bigger and of varying depth so it's acting like a huge diffusor.
Honestly I don't think you could ask for a better starting point.

next goal would be to pop acoustic panels in the first reflection places (probably the ceiling above the TV and maybe the left wall if any is not covered by a DVD Rack (the rack is good as it too acts as a diffusor)

I'm guessing you have a pretty good sounding system right now?

- Jack