The extremely simple solution to sundiving and atmodiving

[Athena]

Just make ships immune to atmospheric burnup, radiation, and collision damage while being flown by an AI helmsman. Make sure to give those things new damage types that aren't used by anything else so that ships don't become immune to lasers or something while being piloted by the AI.

Occasionally getting stuck to the surface of something during a lag spike is a small price to pay for not hemorrhaging ships and time to celestial bodies.