That's gorgeous, Tippler. I'm quite happy with it, meself.
Thought on the highs: try moving the mic away as you move up your range. Most microphones are more sensitive to higher frequencies, and it's especially pronounced on cheap mic.
If you have your mic on a base instead of holding it, turn down the gain and hold it anyway.
This is a very old video of vocal group Rockapella. I'm going to stick it up here, because high tenor Scott Leonard demonstrates most excellent mic control:
EDIT - Also, what vanblah said. I can work much more easily with a track that's too quiet, rather than a track that's too loud. However, ultimately whatever you give us will do. Don't stress too much about it.