I retired about two years ago, and would not changed a thing. I really enjoy being able to have the freedom to do whatever I want to. I am fortunate I can shoot almost daily, and did last year.
Last year, I hunted more than I ever have and it was great. Two elk hunting trips, numerous deer hunts, pheasant and grouse hunting in between - it was just great.
One cautionary note: people will be more than happy to come up with all kinds of suggestions for you to occupy your time - if you let them. I am speaking from experience. Keep control of your time - as Bonebuster said - do the things that are important to you today. Tomorrow is guaranteed to no one.
Good luck and enjoy your free time!