Awright, writer's block has struck, so I'm back here again.
a) Taking damage may work for Street Fighter, but I don't think it would work so well for Smash. Mostly because of the fact that damage does not guarantee death in Smash. For example, on stages w/low ceilings, Meta Knight could fly up of-screen. He would take Bubble Damage, thus filling up his super meter.
Let's say, for another example, that P1 (Bowser) is playing against P2 (Jigglypuff). Bowser is at low damage, but thanks to the damage he's been taking over the course of the battle, his super meter is practically full. He'll get a FS in one more hit. And Jiggly's one stock up. That totally won't lead to Jigglypuff stalling or anything.
Plus, it makes Fox's blaster kinda stupid.
Force Unleashed analogy isn't that bad, because VS in FU is basically a really crappy fighting game. The gameplay is fine, but the whole thing is wrecked by the super meter. But, w/e, I'll drop it for now.
(I always thought Apples and Oranges were pretty comparable; Fruit, Grow on Trees, Round, Have Peels, Can Be Turned into Very Tasty Juice, Both Warm Colors, etc.)
b) It's not necessarily that the current execution/your idea would be too complicated to handle. It's that Smash has always been so simplistic, and a lot of people would like to keep it that way.
c) Considering that very rarely do characters go through major changes, I'm not sure Sakurai would be willing to totally revamp all their FS's. Because, with your super system, a lot of FS's would have to be dropped for balance.
