I know this is heresy, but...

So you may be best just going after the most Bass trapping possible with aesthetic appeal you can in that room and hope for results with your subs

My thoughts exactly. Big rooms are generally better than smaller rooms but they can suffer from very long reverb times in the bass (end to end). Currently a PEQ has all the room modes well under control but my thinking is that it might be better (more natural sounding) to do more with bass traps on the rear wall to dampen long reverb (about 10 feet behind the listening position). I am struggling whether it will really do much to improve the extreme LF?

FYI: I am generally very skeptical of tweaks but following advice on a Genelec website lead me to be pleasantly surprised. The other thing that convinced me was Doug Sax Studio. Doug won a life long achievement award from AES for his work on audiophile recordings (Sheffield labs etc.) and he built this studio in 2004 with soffit mounted speakers in a half wall.

Shadorne...Rives audio, who certainly are great believers in room treatments, will tell you that low frequency problems can't be fixed this way. That's why they developed their PARC equalizer. The only really "correct" way to deal with LF room modes is to build a special room with ideal dimensions and no square corners. But few have the time and money to do this.

You may want to contact Rives or Realtraps. If you buy something from them they'll be very open to advice for you. Like Undertow says above, your system is unusual. I'd try to get the front baffle of my speakers out at least a few inches from the wall.

The rest of you room looks like it would also benefit from some treatment and bass traps. In my opinion you're much better off to get the room much more damped than your room is. All of the reflections are not what was on the recording and too many like that will definitely change things too much in my experience.

Best wishes to you. You may also want to post this over at the acoustics circle at audiocircle.com. Ethan Winer of Realtraps and the owner of GIK spend a significant amount of time there as well as others who may be able to help you better than myself. One thing that is for sure the money spent on room treatment is a bargain considering the improvements. I just read an old article in Absolute Sound where Robert Harley had said the exact same thing.

It's hard to imagine how much it can help until you experience it for yourself. I still like Undertow's statement" The Miracle of Room Treatments". No exageration imo.

Shadorne, you can look at my new system pics I added 16 linear feet of trapping just hours ago, and I am updating the pics right now.. I have no idea of the sound yet as I don't have the time to mess with it yet, however it looks pretty good! you could maybe go look into this type treatment, the Corner wedges with blocks, they come in Brown, red, burgundy etc... and really take up no space, you could do an entire ceiling with pretty good results, not super cheap, but cheaper than most other ways to get around it I would assume.. Auralex is the main brand on them, but I got them direct from the foam maker for far cheaper.. about 200 bucks for it all..Including the 8 24" pieces of trap, and the 2 blocks for the corners and the auralex install kit, which is tabs that do not destroy the foam or the wall and can be pulled down anytime and used in another room over and over again.. Its kinda like an out of control crown molding in many colors! Check it out, might be more acceptable than foam panels all over the walls, and you bass is supposedly mostly concentrated in all the 90 degree corners anyway.

Shadorne...Rives audio, who certainly are great believers in room treatments, will tell you that low frequency problems can't be fixed this way.

The above comment is my worry exactly...I am sure acoustic treatment is essential and extremely beneficial in a smaller room ....but is it effective in a larger room for below 100 Hz? I don't use a PARC but I have a Behringer PEQ controlling or taming the Sub (reducing room modes). On the mains I use some slight bass shelving (about 3 db) to reduce the bass boost effect from the soffit mount. I don't have much concerns in the mid/tweeter range as all the walls have a roughened surface (about 3 to 4 mm deep) which helps with diffusion, furthermore, the speakers are placed well away from side walls (about 4 feet away, so side reflections are delayed about 8 msec which is almost certainly enough not to interfere with primary signal, using the 5 msec rule of thumb for side reflection and diffraction)

Shadorne, you can look at my new system pics I added 16 linear feet of trapping just hours ago, and I am updating the pics right now.

Wow nice set up - your room looks awesome and I bet it will sound great too once you have it all setup.

I appreciate all the ideas and admire/respect what you guys have done.