If I had to do it all over again, here is what I would do differently:
1) I would have cared more. That is sort of obvious for all of us. We do not understand the importance of learning when we are young.
2) I would have studied drums in addition to piano for a few years. Almost every musician I know is weak on rhythm (including me). What I have found is that we are so bad at rhythm that we don’t even understand that we have a problem. But drummers cannot hide from bad rhythm and that is why they are usually far stronger in that area than pianists.
3) I would have studied another instrument in addition to piano (strings or maybe woodwinds). Pianists tend to see music in a vertical way. When we look at a beat in a song, we are looking at a group of notes which comprises a chord.
String players tend to look at music horizontally. They see melodic lines. Over time, they typically learn to play and compose melodic lines much better than pianists do. The ability to improvise melodic lines is a huge weakness of mine right now.
4) I would not have taken off my 20’s. I barely played during my 20’s. What a waste! I should have been looking for good teachers and practicing.
5) I would have been more open minded. I wince at some of my attitudes toward music from those years right after college. A close-minded view of music is not only wrong but will hold back progress as well. My preferences about music do not define what quality is and they do not define what music is right or wrong.