First off, I sincerely thank everyone for weighing in with their suggestions & experiences.
Secondly, you had me spending hours pouring over systems in search of the desired game. While it bordered on time-wasted, it ultimately led me to do more homework on M&M. Then the conundrum of 2e vs. 3e arose.
Finally, I think it all paid off. Initially, I was leaning towards 2e b/c it had more support and stronger linkage to the base d20 system. After researching M&M 3e, however, I discovered that it truly was still a d20 game under the hood. Seeing sample builds of non-superheroes on the ATT forums further cemented the toolkit nature & that not only could it be used for non-supers, it could do it well. I also discovered that the PDF for 3e was available. After making the purchase, I'm impressed by what I've seen thus far.
More importantly, a lot of the streamlining dovetails well with True20 revised, so I don't have to houserule all of the sci-fi elements I'd like & can utilize more of Reign of Discordia with less adaptation than I anticipated (starship combat, in particular).
It'll take awhile to go through the book but I love the fact that it has the toolkit flexibility of a GURPS but is still grounded in the d20 framework that I prefer.
Thanks again to all!