for me..yoda and vader is a MUST!!!the emperor as well.
(yoda vs the emperor would be fun..ie 2 short old guys who are mortal enemy)
in terms of levels i wouldn't mind seeing a saber duel with no force map which is set on a wide,long walkway with nothing below them.
btw how about a saber wielding wookie
he'd have to have burnt fur ofcouse.