No way I would tow anything bigger than an ultralight with an electric-only vehicle. Too many uncertainties when you travel widely, including poor power quality in many campgrounds.
There are some nice gas-electric hybrids that can also tow. Regenerative braking mode helps with grade descent. If you do decide to go the towed route, have you seen the Happier Camper Traveler? It's all-molded fiberglass, made in Los Angeles, and light enough to be towable by something like a Highlander Hybrid or a Lexus RX400H. It can be set up with a convertible double bed/workspace at the back and a single in front. Center galley and wet bath for some separation while work-camping. Might be a wait to get one, though.
Okay, I'll confess I like spending other people's money...