Of the three, Uma is the one I enjoy the most, though I have not gotten as much out of their UK travels as I did when they were in the tropics. That's just me though, I know others love cold water voyaging. Dan is super resourceful and is not afraid to be unconventional, I really like that. Even when I don't agree with what they do, boat work wise, it is fun to watch them try things. I think the electric motor is a monumentally bad idea for a cruising boat, and sometimes they try too hard to prove it will work, but they seem to be getting around it. Sailors seem to have this innate urge to avoid motors, or use the smallest possible motor they can get away with. I don't understand that, but then, I often don't understand sailors, so there ya go.
Some, but not many sailors, don't use motors at all. I know when I was sailing, I surprised myself at how much I could use sail coming in and out of marinas and sail away from jetties. In the above, concerning Ulma, a new or newer electric motor was installed so I guess for them, they feel electric will do the job. They don't rely on the motor for long term transiting, they use it more for marinas, entering and exiting ports, etc. You will be happy to know that they are now back out to sea, destination unknown.
The Wynn's have been nomadic now for ten years, six in motorhomes and four on their sailing Cat. I installed a composting toilet based on their motorhome experience. My understanding is that on their Cat, their toilet is composting but for their guests a more traditional marine toilet is used. In fact the best videos for composting toilets are the ones they put out during their motorhome phase, they have stood up to the test of time.