Your speaker/amp selection = total overkill for the size of the room. I looked up your speakers and they are big units and rated to 30hz anechoic, yikes! I don't believe you could stuff enough room treatment into that space to make a difference. Throwing money at cables will accomplish nothing.
It's time to start over with a much larger room or speakers and amp to match your current room. I have a small room 10x14 for my secondary system, speakers are matched to the room and amplifier to speakers, with virtually zero dollars invested in cables or room treatments, and it sounds fantastic.
It's time to start over with a much larger room or speakers and amp to match your current room. I have a small room 10x14 for my secondary system, speakers are matched to the room and amplifier to speakers, with virtually zero dollars invested in cables or room treatments, and it sounds fantastic.