I'm always interested in this kind of thing. Some people have offered to mix some stuff of mine...but I generally never hear back from them, after going through all the trouble of sending the raw tracks etc. One bloke mixed a song of mine a few years ago...put real drums on it and added an organ pad too. At the end of the day I preferred my original mix...but at least he finished the job. I was grateful. Recently, I've sent 3 whole songs out to a couple of people who asked if they could mix them...and after a couple of rough mixes, never heard from them. Lately, I think my mixes have been on the improve, so I'm not as interested in how someone else mixes my stuff.
I guess my point is....if you're offering, and people take you up on it....make sure you get the job done and do what you said you'll do. Don't get me wrong, nobody was under any obligation to send me back wonderful mixes or any mixes, and I lost no sleep over it...but in your shoes I think it's better to be the guy who gets something done, not the guy who takes the tracks and disappears.
Good luck!