I need help with acoustics and speaker wire

I moved from the West side of Cleveland to Prescott,AZ at 5,400feet. 3 years ago.I have not changed my 2 channel system at all but my acoustics have!! The system which I feel is quite hi end consists of Mark Levinson amp & pre amp and Acarian Systems Alon 4 speakers.This system had a smooth warm and mellow sound with an abundant of tight bass It now has a harsh sounding metallically sound with an overabundance of treble with lots of listeners fatigue!

My old room was a 37' long X 27'wide great room with an open floor plan (open to kitchen & dining room) that was fully carpeted in the 37'X27' room dimension  with a 10'cathedral ceiling. The speakers played into the room depth. My present room is 20'wide X 22' deep and has a hard wood floor & a 10 cathedral ceiling. The speakers are playing across the 20' room width.

I plan to fully carpet the room and move the speakers so they play into the room depth. I hope this will correct most of the sound harshness. Now my problem with the speaker wires. My speaker wire is Mark Levinson HF-2.5c (660 strands of .07mm copper wire twin lead) which I cannot find anymore and the speakers are TRI WIRED! The change of speaker location requires "a "very large amount" of  additional wire and the option of placing the Levinson equipment between the speakers to vastly reduce the amount of wire needed is out of consideration.

I do not subscribe to all of the hype & voodoo magic associated with high end wire making large imagined sound improvements and am not willing to pay the outrageous sums of money required to redo my system with it. The question is this is there a wire that I can add that would be compatible with what I now have at a reasonable price or should I discard the wire I now have and wire my system with Monster cable so all of the wire is the same or some other reasonably priced wire?

Most of you don't have this problem as your speakers are not tri wired and you place your amps between your speakers and your wire runs are under 10' per side so the cost is not an issue. Suggestions please!!??