Sorry about the cancer. Enjoy yourself while you heal or plan.
Body size, leg legnth, back length, arm length, weight matter. Proposed posture matters, forward for efficiency, straight up for comfort. There are bike frame sizing programs on line, use one to pick a frame size, and rise. Some frames come only in one size, that size may not fit you. Top speed matters, length of trips between charges, roughness of pavement or softness of beach sand determine your desired wheel and tire size. Maximum grade matters, mine is 15%, pretty radical. I draw 750 W on the display up those if I start too slow, but 400 W if I hit 15% at >5 mph. Type of mount on the motorhome matters. There are ramp up devices, there are cable lifts from the ladder, there is lift it yourself. Choose now.
For example, I'm 67, needed a e-ride home 30 miles from summer camp if injured (no phone, no car). Plus occasional festival rides of 80 miles round trip without charge. I'm miniature, with short legs, so I was able to take a ninety's kid's 10 speed cruiser and convert it with a powr wheel for $600 (for the 80 mile range battery). 26"x1.9" tires are fine on our roads. Bigger people have to pony up for a bigger frame which will not be at the charity resale shop. Higher speeds than my typical 10 mph indicate suspension built into the frame. My frame is rigid. Snow or sand indicates big tires, 3 or 4". Ultra smooth pavement allows tiny wheels, 16"x 1.5". I wanted pedal assist plus throttle only, since if injured (pulled muscle or tendon) I don't want to pedal. On festival excursions, I can extend range by pedalling. Whatever NYC/California are requiring don't matter to me. If I break a leg the police tell me my $8/mo cell phone will call an ambulance, otherwise Verison service is $70 a month. Park riding in CA or MA or other "civilized" states may dictate no throttle. Stealth batteries and no visible motor may cut number of encounters with park rangers.
Nuvinci 380 is reported to have trouble with higher power motors, it was designed in the leg powered era. Some oil leaks reported under maintenance. I like the idea of 380; the detent shifting of Shimano 7 speed derailleur has given me a big cyst above my thumb tendon. I tried Sturmey-Archer S80 IGH, it has a reliability problem with the shifter cable mount. But the twist grip SA shifter is making my cyst go down. Nivinci is twist grip shifting.
Have fun shopping.