Speaker Cable Upgrade Path Advise, Please

I used to use the Crosslinks, and although there are certainly better cables above these to be had for not too much more money, I wouldn't have described them as "bright". In fact, I chose them at the time because they were smoother than the entry-level Monster and AQ stuff. I've since upgraded to Cross, which actually lets more of the extreme highs through, but does lose the congested lower treble, removing what I would describe as a "hard" sound in the Crosslink. I agree about the somewhat muddy bass, but maybe the "brightness" you hear is actually present somewhere else in the system, and the Monster wire was merely suppressing it? But basically, I would say that Crosslink is just not enough wire in between the DNA 225 and the Sratus Gold's; try a good cable with a guage closer to the 8ga. you were running before. And oh, don't overlook the possibility that bi-wiring may not agree with your setup - this could have been a confounding variable. Good luck!