I bound off 6 stitches instead of 4 for the thumb opening. (I find the larger thumb opening to be more comfortable.) I also added 3 rounds of 1x1 ribbing at the fingers.

The colors in this variegated yarn pooled in such a way as to spiral around the mitts. Since the pattern is fully reversible being just ribbing and double moss stitch (or double seed stitch, depending on who you ask), I turned the second mitt inside-out so that the spiraling is a mirror image of the first mitt.