Choices are always tough, especially if you are buying new...
One of the points I always consider when adding features or, as in your case, picking them, is how they will affect resale value. While certain things are forever, like your first love, (?) first time FGRV ownership isn't always that long lived.
As far as resale, many newbie trailer buyers, of newer model trailers anyway, almost always expect a small trailer to have a 2 or 3 way
refrigerator, a
furnace, a water heater and a stove or cooktop, as well as A/C. (They also seem to expect a garage, but that's another issue) Anything less will reduce your buyers pool and resale price.
While the
refrigerator seems like a big expense, if you are going to use your rig off-line much there's nothing easier to use (and not worry about) than the lp operation of a 2/3 way
refrigerator. And finding block ice away from your home sources just isn't always that easy. Cube ice doesn't last as long and, at $2-3 a day for ice, it adds up. In short, you will recover the extra cost of the refrigerator, and you will get to use it for all those years before selling.
Yes the A/C will require 120VAC, a very elaborate and expensive service to provide off-grid, meaning either huge solar/battery/inverter system or a
generator, either of which will run another $1200 or so. Most A/C's are used only when hook-up power is available.