One thing I still love about SWSE is the way the feats-and-talents system allowed really easy, flexible multiclassing. It was about 1 or 2 steps away from being a truly classless system, and 5e's bounded accuracy would bridge most of the remaining gap.
It was basically the same system as d20 Modern, except "Soldier", "Scoundrel", and "Noble" are way more flavorful names than "Strong Hero", "Fast Hero", and "Charismatic Hero".