Soundstage wide and deep but not at all tall. . .

My system, like myself, is vertically challenged! This relates to another post I just made where I was considering adding a preamp. The shortcoming of my system is that vertically everything stays right at tweeter level at about 36" off the floor. The soundstage extends well beyond the speakers to the side, and depending on the recording extends 6-10" feet back. The speakers totally disappear, and imaging is quite solid. Everything else about the sound is so large and involving, but the "height restriction" reminds you that you are listening t recorded music. This seems to be the final frontier for a system that is otherwise very satisfactory.

System details: Cary 303/200 with internal volume control thru Harmonic Tech IC's direct into Spectron Musician II amplifier. Cardas Goden Cross bi-wires into Totem Forests. Recently upgrade both power cords to Fusion Audio Predators. Room is dedicated HT room with appropriate amount and type of room treatment.
tpsonic, can you please explain why you think diffuse is better than absorption at the first reflection point? I am beginning to try and get some room treatments and this information would be very helpful.
Jswarncke, a good preamp may help. In my experience a preamp expanded the soundstage in all directions. Also, consider some acoustic treatment on the ceiling. If you overdamp the sides and floor, this may reduce the height of the soundstage. Can you experiment with any sort of ceiling panels? Or may be even the triangles(i.e. echobusters or 8th nerve) in the corners behind the speakers? By doing that you may draw the soundstage up a bit.
Another solution - at least in my system - was the addition of a supertweeter to Klipsch heresy III's. The height was raised nearly 2 feet. Very satisfying.
If you lay on the floor when you listen, the sound stage will sound much taller!

Seriously though, I would play around some more with tilting the speakers back at various angles until you get it right (ie. to your satisfaction). I had the hawks (also the Arro) and while they do not deliver the height that my current speakers or in between speakers did, I never got a below the tweeter only height.

While with the Claws, these speakers may not be the easiest to play with tilting back, I would play around some more with this. Also, consider raising the speakers entirely. The Hawks are not that tall and maybe if you can get the tweeters above your ear level, they may deliver a bit more height.

By the way, of 2 out of 3 of my in between speakers, both had an upslanted front baffle for the midrange and the tweeters (Wilson W/P and VS VR 4 JR) and both delivered taller sound stages than the Hawks. But I always felt the hawks did a good job. Do you have them loaded with shot or sand? If not, perhaps you want to give that a shot to boot.
I don't sit with my head by the wall

Sorry - I went by the photos of your system. I would be concerned with what appears to be the placement of the listening position in the photo. That you have treated the wall behind the listener should help.