I made some of my old videos private instead of deleting them to clean things up a little. Once I got TubeBuddy, I went back to some of those old ones and and refreshed my titles and keywords and they started getting views again. Glad I did not delete them. Every once is a while and old one catches fire for some reason, not sure why, but it makes all this stuff a little more fun.
If I were you, I'd keep the videos. If you remove them then you'll lose the views. Also, it's nice to look back on old videos! If you really don't want it on your channel anymore then of course delete or even private it then you can look back on it. Good luck