Or maybe add an electric heater for the cabin to dump excess energy to? (might be a problem in the summer... Hrmmm)

In regard to regenerative braking, in old motor/generator elevators they used to burn a lightbulb to deal with the energy captured in the ascent of the elevator.  [Contrary to popular belief, the descent is what uses the most energy because the counterweights have to be lifted and they're really heavy.]  Maybe electric vehicles can install a giant search light pointing up on the roof of the car to burn off that excess energy from driving down hill.  

BTW - the power converter is an option on Fords other than Hybrids.  My understanding is it is standard on Hybrids.

When you are looking for a vehice to tow your Trailer, what gear ratio is adequate?     

Thanks in Advance.....

It works pretty well on flat ground, even at relatively sharp turns, but it's that rolled curb with an uneven surface the rest of the way to the gate that causes me problems.  In a parking lot, you could drive around backwards all day if you liked and would have no problem with moderately sharp turns.  Using it is also a function of getting used to steering with that little knob.  Like I say, I'm a Luddite and learning new technology tricks for this old dawg is always challenging.

If the back up system was sold as a costly separate option on its own, for my purposes I wouldn't bother with it. 

The back up system uses a checkerboard target on the trailer tongue.  It works really well when the target stays in sight.  But when it looses the target usually due to an uneven surface combined with a sharp turn, it gets lost and you have to either pull forward until the target is relocated or just do it manually.  In as much as I am a devout Luddite, I'd just as soon do it myself the old fashioned way.

Here is a video of the back up system:  https://www.youtube.com/watch?v=tby3A29osDg

The factory tow package is generally far more than just the hitch. In our case (2015 F150), it included upgraded suspension, wiring for the 7-pin, transmission cooler. Ours did not come with the integrated brake controller, but it was wired for it. In retrospect, getting the brake controller from the factory would have been the preferred option.

Sometimes you will get heavy duty shocks and/or springs and maybe a better, more aggressive set of tires. On the higher end vehicles you will often see an enhanced camera system and possibly 'trailer memories'. On the really high-end vehicles I have seen a sort of automated 'semi hands-free' trailer backing system. 

It all depends on the specs of the particular vehicle and the manufacturers options.

Can I ask, what is the difference in buying a truck with a tow package versus having the correct hitch and electric brake system installed yourself by a dealer or shop?

We tow our 2021 R-pod 196 with a 2019 Chevy Colorado with the tow package. Be sure to get the tow package with whatever vehicle you decide on. You want the trailer braker controller, etc.  The Colorado has a 7,000 pound tow capacity so we have some safety margin even with a loaded trailer and stuff in the bed of the truck. We generally carry bicycles in the bed of the truck along with a spare propane tank, etc. We also use a WDH hitch to add another margin of safety. We get 12-14 mpg when towing and up to 30 mpg without the R-pod on the back. Wind and drag are the biggest impact and we try to keep it at 65 mph on major highways. We are are also higher up in Montana which impacts mileage.

Any of the smaller trucks should work. We got the Colorado because my wife could get in it without running boards. Try them out and have both of you drive it before deciding.