Now this is the type of conversation I've been waiting for!
Since you guys already discussed the things I thought about already, I have a suggestion for the ending possibly for the 3rd game. Well, in the start, I'm thinking that the Dark Clone would've been following the rebels wherever they take Vader. And then he breaks Vader out somehow. Then other stuff happens, hopefully a lot of stuff, making the game longer than it's predecessors. Then we figure out if we're controlling a clone or the original Starkiller. Then at the end I think Starkiller and the Dark Clone have to be killed somehow, probably by Vader.
I don't know why, but when I imagine it in my head, I imagine Starkiller and the DC to be fighting each other aboard a ship and Vader firing on them from another ship, kinda like Darth Malak did to Revan in KotOR.
"All too easy."