Any ideas to improve acoustics in this space?

Just picked up some Klipsch 3.5s and a KV-1 to complete my surround system. My surrounds and subwoofer are from the Klipsch Promedia Heritage 2.1 system, but running them all off of a Pioneer VSX-832. It already sounds better than anything I've ever owned before, but wondering what I can do in the space to make the most of what I got, like sound panels or the like.