A little more toe room would be better, I used 1x4 rails. Bevel rip your treads to match your pitch makes it much more comfortable.
You're not much older than I am Bob, and see no reason to slow down anytime soon. Major change I've made over the years is to stop chasing money and do what I want.
My ladder was built so I could install that copper. On my shop roof, the stovepipe only gets cleaned yearly, very little creosote even then. Dry wood, hot fire, you know the drill.