I think it would be great. I'd love to do a spy game - Avengers style or even John Woo's take on Mission: Impossible - or something. But i lack both the patience and the budget to take on SpyCraft. True20 would rock the house with this.
I'm thinking it would need to formalize some rules regarding guns (of course) and how they fit into the Weapon Training paradigm. (As far as autofire goes, I suggest the M&M approach, q.v. here: http://www.mutantsandmasterminds.com/super-vision/000213.php
Gadget rules would also be important. I rather like the d20 Future ones, but I'm sure M&M and other resources (like the concentrated Inspiration/Madness of this board) would do well.
If you have ideas, GoRocket, I'd like to see 'em. If i think of anything, I'll be glad to contribute. (at the moment I mostly am thinking of things I already posted in the House Rules thread, regarding an easy-peasy approach to ammo, but other thoughts may crop up later.)
No kitten is going to tell me what to do. I'll fall off this branch to my death if I feel like it!