i dont know much about scripts in skyrim, but i would assume a script could be attached to certain item sets that would make this possible. You are correct, the mehrunes razor is a shining example of such, I think the wabbajack is too. In anycase unless they have unlimited charges they are scripted. Mehrunes only sometimes gets an instant kill, something I doubt an effect would be able to accomplish and when you do instantly kill something just like every other hit, the charge meter doesn't lower. Besides they did this sort of thing in Oblivion with a few items. I think there is much potential for this mod as far as concepts are concerned.