Well, by definition, if you got into better physical shape, you'd feel better in 99% of the cases.
If you then expected that to guarantee you'd find the man of your dreams, you'd be rolling the dice instead of making a good plan.  Yes, your physique would likely help you, but it doesn't do much good to hook a 10-pound bass if you're fishing with 5-pound test fishing line.  The physical is only the badge that gets you in the door, and just like getting a new job, you have to then perform to expectations.
Gay men are a tiny minority compared to the straight population. It is always going to mean dating is more of a challenge and it will always mean lower odds of success.  Unlike racial minorities, we cannot just see the other members of our group on the street and know we are us. 
Become the person you want to be.  That may be educated, productive, fit, artistic, horticultural, musical, or whatever, but you know in your heart what that is.  Follow your bliss, and don't be mislead into thinking someone else has the key to your happiness, not even your lover.  At least half the straight population in the US has already learned that lesson the hard way and is either divorced or in the immediate family of a divorced couple that once was in love.
As for what I want, I'd like to find Mr. Right, but what I want most right now is to get on my feet in my new home, get repairs completed and begin entertaining like I did a decade ago.  I like playing cards, having friends in for dining, and games.  My goal is to get all my nest made here, make to retirement, and hope to live another decade after and die at the average age for men in my late 70's.  I think a decade after retiring will be plenty of leisure during decline.  That's my 20-year plan.