Pelo, the Japanese spec definitely wont work in the US but I am thinking about having it modded with a different transformer and then while I am it having other parts modded to improve the sound. The total cost will still be cheaper than buying the US spec version.
I would love to get the Luxman DA-06 for that price! Unfortunately to make it work in the US you will need a step up transformer. I am not certain if that would impact the sound otherwise I would get the Luxman. I have the D-06 cdp and love it!
As mentioned you have nice gear but it looks like your room layout is challenging. Before changing any gear I would work on room treatments and power. In my experience these two things impact the sound more than changing any component other than speakers.
How far away from the speakers are you? As recommended by Milpai I would consider some room treatments, especially behind your listening position. When I added absorption to the wall behind the speakers I got a more naturally warm sound with much better layering of the music (i.e. I could "see" the singer in front of the drums)
For power, are you just running everything off the standard wall power? I suggest looking into a good power conditioner or regenerator. I myself use the PS Audio P3 and was amazed at the improvement it made to my system. Adding nice power cords also helped as well.
