A couple of improvements.

Enabled AA, everything looks smoother.
Whenever you zoom, it zooms on the mouse.
When zoom is < 1, and the selected planet is in view, it locks it to the planet.
Period (or full stop key) will now centre the camera on the selected camera.
Fixed the title. :P
Added mouse position to debug menu.
Testing resulted in 16 being indeed the best choice. But since it rips down my framerate, I leave it at 0 during development, since it would hide other performance issues from me.