Our perspective on powers implementation was pretty static by the time we got hit with our 4e enthusiasm. That said, I was for a while influenced by the "permissions" concept in Wild Talents, but our DF implementation of that turned out to be a little too cumbersome. Digging deeper on the roots of SOTC, we were definitely influenced to an extent by Exalted there, though I think the fingerprints of that have faded by the time we get to DF.
I'll try to think more about this question and see if I come up with anything more.