The major problem is that in effect you would not be the person your are presently.
so?
If I had made different choices in my life, that replaced the ones I really regret, I might not have have met my wife, nor many of the wonderful, dedicated Christians that now are so much a part of my life.
So, if I could go back in time, yes there are choices, and actions, I would change, but not those that I learned from, nor the discipline the Lord used to bring me closer. Yes, there are those I would ask forgiveness of, if I could find them. There are also those who I wish I could go back and praise for their wisdom, and their love that has brought me to this time in my life.