I think you make a very good point. I wasn't close to my grandparents and I would very much like to have heard about their lives. My mom and I had a close relationship and I'm glad I don't have a bunch of videos for exactly the reason you say -- it would be too much
There's an interesting This American Life about a person who's mother left a pile of letters to be opened once per year on the daughter's birthday, and one for her wedding. It started out very good, but ended not so great (see Act 1) ("... you shouldn't be dragged back into the grave with them every year
So I started this post, listened again to that TAL episode, and coming back to this post, will sort of disagree with what I said at first. I still think periodic mailing is a bad idea, but maybe the poster could make the videos, but they would be given to the daughter immediately after the funeral, and in a whole pile all at once (backups kept somewhere in case of accidental or intentional destruction). Then in the future, if she chooses, she can watch what she wants -- all, some, or none. This leaves watching as a choice she may or may not exercise -- in contrast, the periodic shipment seems like it has a good chance of becoming a source of resentment and pain (i.e., why should a ghost appear on the wedding to potentially create great sadness or feelings of being a disappointment or whatever).