"My system is in my living room and those tweaks would not pass WAF."
Having invested many, many, many $1000's in cabling and less than $1000 in DIY acoustical treatment, my experience is that all make a big difference, but the acoustical treatment is the hand-down winner in improving your sound the most and for a pittance compared to good cabling.
Try the Cathedral Sound panels from The Cable Company. They are the size and shape of a laptop and are covered in an inconspicuous light silvery-grey fabric and can be spray painted to match your wall color. They go in the top corners of your room, one in each of the front corners facing forward and one in each of the rear corners. Total cost is less than $400 for two pairs.
While not effective below 80hz, they will work wonders to clean up the mid-bass and lower midrange and only have a small effect on the upper midrange and highs. The only way I know of to improve <80hz frequencies is to buy/build large acoustical panels (like I did) or Tube Traps and it sounds like your wife is not good with that.
As for cabling, first establish a "foundation" with your AC delivery by adding:
1) 20A dedicated lines from your breaker box to your equipment using 10 gauge Romex and separating digital and analog equipment between the lines. Cost should be around $500.
2) Audio grade receptacles. I prefer the Teslaplex ($95), but also like the Porter Port ($36 here on Agon), many swoon over the R1 ($145) also.
3) High quality power cords, starting with your source. Good cords start at <$100 (like the Pangea cords from Audio Advisor) and great cords cost $1000's. There is most definitely a difference. If you can't hear it in your system, something is wrong with your rig, your room, or your ears.
When upgrading cabling, initially have your existing cables "cable cooked" by someone who offers that service. Then move toward improving speaker cables, then IC's (starting with your source), in that order, cooking them as you go.
Hope this helps. Good luck.
