1e has more career paths than 2. It includes specific skills based on the home world chosen. It mentions groups like Loki. It includes cramped barracks for half spaced lodging on ships. It has a Sword Worlder bonus on aging due to the vitamins and limited anagathics in their diet: + or - End bonus to aging roll.
2e has more details about the world/systems and a missile system for SW ships. And better maps, I think.
I got, and use both.