It's pretty, but shallow.
Combat is pretty, but very shallow. The class of your ship doesn't really do anything other than increase your size and weapons. Shooting is performed along the same lines as a on-rails shooter, its just you control the direction of the rails. It is the same formula of X enemies together peel the outside ones off one at a time. Equipment is essentially a level check, if you are under-leveled you are outclassed and won't make much progress against targets.
There isn't that much variation or many interesting choices when it comes to combat. You try to line up shots with your maingun on a 1D line (target leading handled by eye, with poor visual feedback on hits), while holding down the subweapon firing button. You can switch it up with continuous firing guns or maxing out turrets, but you can't drive and shoot turrets well at the same time. The combat doesn't really change once you have all your modules filled, that's what its like forever.
Trading has the problem of procedural generation being used without finding the heart. You take Good-A from Station-A to Station-B. You take Good-B to Station-C. You take Good-C to Station-A. Repeat. Occasionally there are sales on goods to increase your profit margin. You can disengage from virtually any combat so there isn't any risk, just time spent travelling and offloading/onloading goods.
For Space Sims I think Space Pirates and Zombies (SPAZ) is probably your best current game, with SPAZ2 being an option with its early release on Steam.