Cool project, but I gotta ask; Why karo this?
Is it baffled or sewn through? If it's sewn through, you've basically just reduced the warmth of this by having all those stitch lines, if it is baffled karo walls, then it's a good exercise certainly, but a lot of work for something that really doesn't need that complexity at all.
Honestly a mitt is so small, you don't need any separations at all except at the thumbs imho.
Either way, cool project, but I'm going to probably file you in the masochistic folder. :p