I usually don't complain much about my monitor mix. I usually tell the soundman what I want in my monitor, and leave it. In the same way that I've learned to hear the bassline in a song on the stereo, I've learned to "hear" the thing I need to listen to from the band, regardless of the monitors. I try to isolate the vocals or whatever from the other instruments on stage in my head. Does anyone else do the same?