You forgot the UV material!
Chauncy Lively (Absolutely no relation to the "legz") tied very realistic nymph patterns with legs he would make from tying thread and flexible cement. His flys were beautiful, but I don't think even he would have argued that realistic legs were necessary. I think legs on nymphs are important, but the movement of the legs trumps appearence. So I would rather use a bit of partridge or grouse and have it move than use a perfectly sculpted leg with limited movement.
The problem with new fly tying material is that it is hard to make a fly useless by introducing a new material. If you have confidence in your hare's ear nymph, you will probably catch fish with a squirrel nymph or even a synthetic dubbing nymph tied to the same profile, and you might even catch more if you belive you have a magic squirrel hide. My guess is that legz, uv material, glow in the dark et al. are magic squirrel hides.
Mike.