X-Wing alliance honestly kind of sucked. Entirely too much focus on the Irish Space family drama, not much really interesting with the rebellion, and then for not adequately explained reason you turn into Lando Calrissian for the last mission.
While I'd certainly pay for a remake of TIE-Fighter, I'm not sure I'd pay $50 - the missions were epic and all, but in retrospect the star wars space flight sims feel awfully constrained compared to something like Freespace. Only 2 primaries, and like 6 secondaries. There's just not all that much actually there.
As for Endor, and Endor-like situation might be interesting, but the actual battle of Endor would be awful. Everyone knows the score, so the entire imperial team is going to camp that entrance like you wouldn't believe, and you can't count on Storm Troopers and Tie Fighters in a multiplayer game to have sudden plot-induced stupidity and awful aim.