| This looks excellent - like 3e5 skill tricks without having to but the option. As you say, these are the sort of extraordinary things we'll want skills to be used for occationally. Occationally => I like the -5 for repeated use.
There is one thing, though, that I do not like. Some of the Stunts seem like no-brainers to use whenever there's a chance; Unwinded (End), Knock em Down (Acr) especially seemed like this. Knock em Down also reminds me of the common flaw of critical-miss rules that more attack produce more natural 1s but I don't know how bad it would be in practice.
KeD (and a few others I don't remember now while typing) also seem out of line in that they do something to an enemy without beating a DC relating to that enemy. That doesn't seem right.
Anyway, I really appreciate the thought you have put into this and will certainly present skill uses such as these to my players once we have played the generic game enough to be ready for extra rules. | 
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