OK, here's the second half of the side stitching. The tension was much better this time around, although of course the sides of the mouth are slightly different lengths as a result.
I had two goals with the second half: experiment with adding a little ear to aid in opening the purse; and see what I could do about hiding the unfinished end from the first half. I cut off the knot and buried it between the fabric edges. This mostly worked, but was a little sloppy, as the corner was difficult enough on its own.
Another idea I had a while ago, which Rebecca reminded me of, was the fact that these ends could be turned into tassels or covered by knopps of some sort.