I've been working on a pair of slippers last week, or 1 slipper actually. I already frogged the first version, and now I made some progress on the second version. This is how it looks:
I doesn't show a clear structure yet, but the idea was to make an insole and an outsole, in between which you can place some reinforcement. I used heel stitch to make the slippers stiff and durable.
I'll try to show you some progress soon.