Or...you could do a full size truck build and tow an atv/dirt bike trailer. Go anywhere you want on the bikes and go any reasonable place with the whole set up. I saw a sprinter that was set up to accommodate two bikes and had living space. Seemed like a pretty sweet set up.
I have considered bringing a motorcycle and it is on the table. I do have a Triumph Tiger 955i + utility trailer.
I'd definitely steer clear of a full size American vehicle if you're planning to overland aboard. Diving through Europe in a Tremor size vehicle would feel like driving a semi. Narrow lanes and big vehicles would chew into the relaxation factor, not to mention the fact Toyota parts are available on every continent bar Antarctica. But this is obviously a landcruiser forum, we might be a bit biased.
I drove 40' transit busses at one point in my life, so I am not unfamiliar with driving big vehicles through tight spaces. The concern I have is if it can physically fit.
Side note on blue water cruising - you'd be surprised how lonely/ boring it can get. The pictures look great on Instagram, but the reality of being anchored in a mosquito inundated bay in Tahiti for three weeks (or months) with no ac and not much to do wears on all but the most dedicated couples. I love the sailing part, but in a cruiser that needs to dodge weather you have surprisingly small windows to actually move around, unless you want to roll the dice with your life during hurricane (or cyclone) season. If I was going to do it again, I'd fly somewhere, rent a house and a car for 3 months at a time and be less shackled to mother nature.
All good points. I know sailing is ~95% not sailing. I still couldn't convince the wife that there isn't actually much sailing in sailing.

It is short periods of high stress followed by long periods of boredom.
The big positive to me with sailing is that it is new and different for me, which means active learning. Active learning keeps the brain healthy.
Originally, the plan was to sail and then overland. I think sailing might be harder to do after overlanding because people are less likely to try new things as they age.
An acquaintance of mine got their Earthroamer (F-550) stuck in Costa Rica with big drivetrain problems with 6 months/22k on the clock driving the Pan American. They waited literally months for Ford to ship warranty parts and the local Ford dealership to repair it.
The one thing I have heard about Ford's Diesel, which a Earthroamer surely has, is that it is extremely complicated, with additional emission controls, and can be prone to issues. Sure, you can drive it to 500,000+ miles, but not without issues and $$ service. This is why the new 7.3L gas motor is attractive to me. It is simple, under-stressed and it is designed for commercial duty. Whether it is well designed, who knows. That will take years to know. I have faith in the rest of a Super Duties drivetrain, except maybe the new 10 speed transmission. That might take a few years to know as well...
I will say this, I have had better luck with Ford motors than Toyota motors. I am comparing pre-2001 Toyota engines to post-2000 Ford engines. Apples to Orange comparison but it is what I have to work with. I have had countless head gasket problems, starter problems, and fuel pump issues with Toyota's, all between 90K to 125K miles on the motors (multiple 22r-e, 1fz-fe).
Many manufacturers had HG issues through the 90s, including Ford. Since 2000, we have put 650,000 miles on Fords, I have yet to have a single issue with a motor, or any other issue besides wear parts. No HG issues, no starter issues, and no fuel pump issues. My commuter car is a 2010 Ford Focus with 180,000 miles. My wife drove a 2007 Ford Fusion AWD 3.0L V6* to 350,000 miles. That motor in her car still sounded new at 350,000 miles, with the original exhaust, transmission, transfer case, etc.
I posted here long ago when my LX450 water pump failed on a camping trip, and I was unable to locate that water pump at any nearby Toyota/Lexus dealership. (edited to add that I also tried local auto part stores). I was in New York at the time, not some distant 3rd world country. The closest Toyota dealership tried to tell me that they don't service Lexus...and once I convinced them it was the same engine, they said it would take a week to get the water pump.

We made it home, with the bad water pump, but only due to my ingenuity. YMMV.
*
Later versions (3.5L) of that V6 did have water pump issues, which would leak into the oil pan, despite double seals, rather than externally. They fixed that design a few years later. We only traded in the Fusion because General Motors gave us an offer we couldn't turn down. We ended up buying a $42K MSRP Chevy Volt for $20K net. We still drive the Volt and it has 130K miles on it now.