There is already one in place. When you turn around your ship, you can use your main engine to stop. Also, there is some bug (or feature?) that allows you to change direction of your flight to opposite direction in single instance without slowing down. (probably because this game uses semi-newtonian physics)
There is amazing mod out there in mod section, which solves this issue, you should check it out :) Although I agree that this mod should be part of main game.
Not bad idea, but quite redundat, as you can build your own ship from preset and just recruit a captain in it. It would make it easier though, and would make sense if your "buy not build" idea was also implemented.
There is mod for this feature aswell, allows you to "dock" from 0.3km
Is already on devs to-do list I think :)
if you select multiple objects, you can unselect some of them, by holding ctrl and clicking with middle mouse button (if that is what you meant)
In graphic option, you can untick "bloom" and all thrusters and lights will be much less pronounced and visible. Solves the problem quite well, but I agree it should be toned down overall.
I pretty much agree with all other points :)