I'd say start with goat. Lots of GOS opportunities and some good odds LEH's. You can do it on your own and getting goat info out of HBCers isn't that hard!!!
I did some backpack goat hunts a few years back while I was in my mid - late 40's in the East Koots. A couple with my best friend and a couple solo hunts.
I trained very hard for them for months and months before the trip yet never felt like I was in good enough shape after a hunt. But those years were the best years of my life health wise as I was fit, focused and goal oriented.
IMHO, goat hunts are very hard on the body and it takes allot of mental toughness/stubborness whatever you want to call it to climb those mountains day after day after day. But it is all worth it and without a doubt the most rewarding hunts I've ever been on.
If my last goat hunt just so happened to be the last hunt I ever went on, I would of been a good way to end it (and I never even got a goat).