Galaxy On Fire 2 and Warpgate are both pretty good space sim games- with trading, combat, mining, and faction systems. GOF2 is better imo.
Elite and Frontier were both totally ahead of their time, and it seems ahead of ours too I played the second one a lot on the Amiga and there hasn't been anything close to it since: a galaxy with stars, planets you can land and explore, realistic mechanics and orbits... even if they'd only release an emulated version with good controls, I'd be happy
