I have very few regrets. There’s been a few people I wish had died before I met them, And I know that when I die, my biggest regret is going to be that I didn’t have time to write everything I wanted. But then, if I do live long enough for that, I suspect I’d be into the third millenium.
By now I’ve mostly outlived my enemies anyhow, another one died last year and they were younger than I am.
For years the title of my apazine was Dum Vivimus Vivamus. Strictly speaking this translates from the Latin as “while we live, let us live.” I’ve always translated it more informally, as “raise hell while you’ve got the strength.” I have, and I’ve few regerets about that.