giant.robot
Adventurer
Prime Directive with different rules (not GURPS or D20) could be interesting. The SFB universe has a lot of fun lore and could make for a very good RP setting.If any, Arrowflight 1st edition and Prime DIrective 1st ed - both spiffy d6 dice pools doing things differently. Both deemed not worthy by their ownership.
I have in the past owned all three rule sets for Prime Directive and enjoyed none of them despite liking the premise of the game.