Well, I would disagree as far as getting lost in the background. Background (as the word implies) is not as important as the subject matter (foreground).
The background is not really important. What is important is your subject being separate from the background to be able to distinguish your subject properly. Otherwise you just have a head and two arms floating in the blackness.
I did bring a WhiBal Pro white balance 18% gray card for White correction so what you see is matched with that card. (note EXIF is listed "custom" for white balance.)
WB gray cards can produce off images when using custom WB. so that would explain why it looks on the cooler side. Custom WB just means AWB based on the gray card shot but is applied to all other images with custom WB. This leaves room for error on the cameras side.
There are more shots on my site in this album if you want to check them out. they have fewer flares and mics in peoples faces. I just posted these since they seem to have some more character. http://www.stockhammedia.com/photo/concert-photography-album-1/
And i'm really not trying to bash your shots and i more than understand that there are some tight situations where you have very little control. That usually means no-so-great shots. i would recommend doing some post to bring out the torsos of your subjects and maybe warm them up just a bit. and i am on a brand new 27" iMac which is know for it's incredible image quality and color rendition. so I'm pretty sure i'm seeing these images properly.