Fascinating story, Tom, with some parallels in my own family, so a little digression.
In high school, I wanted to be a police officer. Later, I ended up teaching them public administration so they could advance through the administrative ranks in their departments.
My Uncle Keith always drove truck, first heating-oil deliveries, then hauling syrup for Coca-Cola before making longer runs for a regional subsidiary of EXXON through a four-state area. He frequently packed a bike on a rack behind his sleeper cab so he'd have a way to work the kinks out of his legs at rest stops and to go in to the truck-stop store when parked on the fringes of their sometimes very large lots (like at the Little America stops). He found it was the constant sitting while driving combined with road food that took his physical conditioning and the bike is what pulled him out of it.
My father took early retirement at age 63 after 30 years in accounting/auditing, which meant he was deskbound for most of his career. On retirement, he wanted a pursuit that would take him outdoors, but without the shock of running. Looking at my interest in bikes, he got one and went touring with me. Our last tour together was a wilderness one, the week before his 74th birthday. He's 95 now, and the doctors think his present generally good health still reflects his earlier, post-retirement exercise. The point being, don't despair! Things may not feel as firmly in place as they once did, but the good news is how amazingly quickly one can become fit with even modest, moderate cycling whenever the opportunity presents itself. You're taking all the right steps to make it happen (again), Tom. That good structure will be the framework on which firm muscles redevelop. Age is with you, and you've not that far to go to get into "fighting trim" again, so all encouragement your way.
As for bicycle gearing and torque, I often think of my output like that of a little diesel -- high initial torque from rest, then a real narrow power band I can stay in by shifting through a myriad of gears (...and, I have been known to make "Brrrrt-brrrrt-brrrrt" noises as I start pedaling and shifting, to complete the effect). I really do find I deal with the same issues you do when trucking, trying to balance weights and torque. This last test-tour was a "heavy haul" and was much different from a "short hop" or "local delivery" in terms of my speed and the distance that allowed. There is a fine line between weight, speed, and the distance it allows. If I weren't so risk-averse in truly remote areas, I could probably go with a very light bike and load and make a good, consistent 125mi/200km day after day and do it with far less food and water carried, speed and distance making the difference. The analogy would be the ultralight through-hiker who "cleans" the Pacific Crest Trail compared to a more heavily-laden backpacker who might not have access to mail drops for resupply and so carries more of his own.
There's a real balance to be made between the two extremes, and I'd always done my past tours on road bike-based tourers with 700C (or earlier, 27") wheels and skinny, high-pressure tires. As I came to do truly self-supported solo tours in remote areas, the need for greater supplies and safety margins became apparent, and I moved to the Sherpa, then Nomad to support this very different "touring lifestyle". Going solo on such trips means going heavier, 'cos there's no one else along to split the load -- the entire weight of tent, stove, fuel, cookware, and tools are all hauled by just one person. To offset this heaviest sort of touring, I've assembled my "SOL Kit" for emergency use and casual overnighters (or even several nighters, provided I can resupply with food and water) that will get the job done (hot food, warm, dry place to sleep) using only my rear rack and a rack-pack for as little as 8lbs/3.6kg. Just a couple days ago, I upgraded the 29 year-old Blackburn alu rod racks on my blue rando/touring bike to Tubus Tara and Logo Evo so I can swap-on my Ortieb bags without the hassle of changing adapter shims. I won't be using a handlebar bag, just the four panniers, and the only rack-top load will be my one-person tent, sleeping bag, and pad carried inside the rear bags with rain gear and minimal clothing. The frame will carry a more modest 2.75l of water (compared to the Nomad's 6.5l), and I'll carry only my little 21g beer can penny stove and alu bowl set compared to my Coleman Peak 1 multi-fuel stove, a liter of fuel, and my carry box/cookset. The heavier stuff is actually more weight efficient considering the greater energy density of white gas or unleaded petrol compared to alcohol and longer time away from resupply, but in the short term and for fast-and-light, the ultralight kit has the edge, allowing me to cover far more ground in a day. The blue rando bike is perfectly happy touring with a maximum of 18kg, so now I will have both ends of the touring spectrum nicely covered.
In the end, it is horses for courses, and the Nomad surely is doing well at the heavy end of things while remaining usable at the upper end of the all-rounder spectrum. Ride quality/comfort is very much determined by tire pressure and volume, but all seems good with nice stable handling throughout. It takes awhile to really "learn" and trust a bike, and I feel I'm building a relationship with the Nomad by the day (and ride). Remember, this is my first bike of this sort/weight-carrying class, and my last new bike was an '89 model purchased in 1991. Before that, the latest was a purchase made in 1984. Except for the occasional frame I might hobby-build, the Nomad is likely to be the last bike I will purchase outright for the next 20 years. I'm 53 now, and that would put me about where Dad (Jack) was when we took our last tour. Something new will come out by then and is sure to catch my eye.
Take care Out There, Tom; very nice to have you aboard as well. Each member contributes, whether with questions or answers, and we're all the richer for it.
Best,
Dan.