Seems like it'd be a lot of hassle for skinners for not all that much use, interesting idea but I'd say it's too much effort for what it's worth. Also, there's a hit error indicator that you can enable in the options that displays how far off the ideal timing you are, although I do understand that it's at the bottom of the screen and it'd be near impossible to keep a constant track of it during a song, but the point I'm making is that something to show your hit accuracy has already been implemented (pretty recently too) so this will probably be rejected.