As it stands right now, despite the drone ship's existence in-game, it is EXTREMELY difficult to do a SpaceX-style landing unless you ditch the second stage, and all but impossible to both recover the first stage and get a half decent orbit. It would be a lot easier if craft (that you're not in control of) didn't despawn, at least while the flight is in-progress, until after they hit ground level. I recognise it could add lag, but at the same time, if the part is simply not rendered but rather represented as an icon on the map screen (as all other craft in orbit or on the ground are), it could reduce the amount of resources used.
I don't think this was suggested prior, I did see one post that might have been suggesting something similar, but it was vague and if my suspicions are correct, it's not suggesting exactly the same thing.