I retired early and ended up going back to work part time. I didn't complete many of my projects, but that's not why I went back. Most of my projects were things I wanted to play with, not things I expected to finish.
Working part time is nice because of external pressure, but really, the most of the pressure is cause I'll feel bad if I disappoint the people that are letting me work with them.
I don't feel bad if I don't get my personal projects done, because nobody is going to use them anyway.