It's easy to say there will be a SFH3, but not any time soon. How? The storyline, that's how. In the first one, we kill the "original" Globex leader. In the second one, the Scientist says that "Globex is comprised of clones. Always has been." That means that in the first one, we either really did kill the Globex Leader, or one of his clones. I'm opting for the leader, since it seems in the second that all clones have red eyes, and the Globex Leader in the second has red eyes. How are we supposed to know how many other clones the leader has of himself?
I think I speak for everyone when I say that there's going to be, and should be another strike force heroes, but one function I would like to see would be multiplayer, I personally think that would be really fun, even some sort of LAN thing would be ok