I'm in my 50s and think about my remaining years too. Based on my family genetics, etc. I probably only got 15 years give or take a few left. I also want to finish strong and well. No matter our age, everyone should take a hard look at their life. No one is promised tomorrow.

There is a book by Bob Buford (sp) called Halftime which is about the very topic you post. The first half of our life is about building and doing stuff, the second half is about significance. He was very successful in business and changed his life at mid life and what he lived for. I have read it years ago, its a very good read for where you are; I'd highly recommend it. I've written a few books and one was called Engineered for Success about how we were made for success in our work and life and how to go about it. It is not on the market any more or I'd tell you to check it out.

None of us will ever find full significance in this life when we live with 100% short term focus of our life and significance in this world. Solomon was the richest and wisest man to ever live. He wrote Ecclesiastes which is a lament on the very topic you posted. He had it all and he came to the conclusion that everything is meaningless outside of knowing God. He summed it all up at end of his writing Ecc. 12:13 - Let us hear the conclusion of the matter; fear God and keep his commandments, for this is the whole duty of man. Not sure what you believe about God but I'd recommend reading Ecclesiastes and the gospels (Matthew, Mark, Luke and John) for starters.

By the way we all live, we may all leave a legacy thru others - our kids, family, friends, etc. in how we lived not so much all the accomplishments. Most of our accomplishments will be washed down the drain a few years after we are gone but our soul will remain forever somewhere. My advice for all is to seek God while He may be found. We can't do anything about our past, but we can do much about our future.