I occasionally play a game called Space Engine, which was primarily designed as a procedural universe simulator. The ability to fly around in spaceships was added later. The developer did decide to include a bit of "future tech" - namely warp drives and extremely powerful engines with no fuel limits. But you still need to carefully consider your maneuvers, because the game indeed uses [mostly] accurate physics. In fact, you can use the standard formulæ for real-world orbit calculations in-game. The difference being that there are no enemies to try and outmaneuver. But you can still get yourself into trouble if you're too near a planet or black hole, etc.
The thing is ... that's exactly why I enjoy the game. Because you can plan complex maneuvers - including orbital rendezvous and docking - without having to worry about someone shooting at you. I always did wish the developer would add the ability to include objectives or some type of scenario to complete. So it looks like Flight of Nova might be right up my alley.