Well since LA/LEC f... things up greatly with X-Wing Collectors' Series, I'd like that to be remade on first thought. It was such a promising product - but replacing the great MIDIs especially of Bajakian (T/F) with digital CD audio really destroyed the atmosphere.
They should make a proper DirectMusic variant of the games and include any cutscenes they left out.
Dark Forces would certainly be great but at least we have the Mod Project for JK2 regarding that.
Rebellion/Supremacy could be interesting as well since it featured quite weak in-game 3D graphics.
My 2 cents for the time being.