From your photo, it looks like your setup violates just about every "best practice" for how to set up a listening room acoustically. Multiple hard reflective surfaces in the most sensitive areas, etc. No amount of gear changes or upgrades will overcome poor acoustics. Best recommendation is to invest some time in any of the many publications available (RH's bible for example) on the do's and don't's of setting up a room for good acoustics.
J.Chip
J.Chip