It's definitely a tough room, particularly with the WAF. Anything you could do to get more symetry would be great (moving the display case, etc).
Would you consider putting your speakers/system along the long wall (in front of the window)? As it looks in the pictures, I think your listening position is too far from the speakers given the space between the speakers to get the best out of the system. Putting the speakers along the long wall would let you space them a little better, and it would put your listening seat in a more ideal location to enjoy things.
If you can't move them to the long wall, I'd suggest the following: the black leather chair is crowding your left speaker, so I would move it to another room/location. Also, not sure if your speakers are rear-ported, but if they are, I'd move them further from the wall to give them some space. Is that painting between the speakers in a glass frame? If so, I'd suggest eliminating the glass and putting some acoustic foam (maybe 1", although thicker would be better if it can fit) behind the painting. Some kind of broadband absorber in the corners would be helpful (since you have a WAF, I'd look at Bass Busters from Echo Busters).
My two cents...