X3: Terran Conflict

It has everything you'd want: A LOT of different ships to fly, exploration, itemization, complex economy, several factions to interact with different personalities and likes/dislikes, build / take space stations, stuff to do / explore even late in the game and a huge amount of freedom in what to do.

The depth to the game is huge, and it also has a huge learning curve which is not helped much by in game guidance, however stick with it, get used to the basics and eventually you will start to pick up new and interesting features, and half the fun is about trial and error!

Trading is alright, just like combat, and it's a totally viable option too.

This is of course an older game but the graphics aren't all that dated - I still love it.

The sound design, including an atmospheric soundtrack and dynamic combat noises, further enhances the experience, immersing players in the vastness of space.