This is probably already buried somewhere deep and forgotten within the colossal to-do list, but I think it bears mentioning. I was disappointed to find out that crashing straight into the super-hot "surface" of the sun appears to cause no damage whatsoever to your ship; instead, you get stuck in the very center of it because of the gravity well. I'm also surprised that the sun sometimes barely even stands out among the background stars, despite it being much closer (although it appears to be a giant yellow and white blob from a VERY close distance...a distance at which your ship should be taking some serious damage - autopilots should be set to avoid coming that close to stars). I understand being far away from it, but even at an extreme distance [in-system], it should be glaringly bright, as you are receiving a huge amount of unfiltered light. Obviously, the cockpit's windows would have something to protect from the glare slightly (thus preventing it from being wayyyy too bright for players), but I think it would be interesting to have stars produce a semi-realistic amount of brightness rather than just being a big sphere or dot with a small, flat yellow aura around it.
Planets should be brought up too. Crashing into them produces unusual results (which are probably well documented) - their mesh completely disappears once you are very close to them, and you suddenly appear to be destroyed by nothingness once your "altitude" reaches 0. I understand that actually rendering planetary surfaces is beyond the scope of the game [thus far] but i think that it would make sense to render an atmosphere around certain types of planets that can damage your vessel (maybe only if it's a particularly large, space-only ship) and to fix the weird disappearing mesh so that you have a surface to visually collide with. Maybe one day the game can even use randomly-generated height maps for the planets' surfaces?
One other minor thing: docking with a planet requires you to be extremely close to it, which is time consuming because the SPEC doesn't work at that close of a distance. Maybe increase the distance you can dock from slightly?