Hard Drive,
The first line of your post described me to a T until my 50s. Then I got together with some friends who were "playing out" and I've been gigging for the last 16 years, mostly solo for the last 10.
Regarding your old Yamaha, set up of an acoustic guitar is so subjective. Even something like the thickness of the neck can make a huge difference to a player. Glad you found a guitar you like to play more. That Martin looks sweet.
My musical heart belongs to my old Yamaha FG 580. I bought it 30 years ago from an old guy who had it for twenty years. He played at dances and it was played hard. It was a mess when I got it, but with some TLC it proved it was a better guitar than I was a player.
Play on!
Best
Les