With Cg near the gear to begin with, is there any reason an aicraft can't be designed to be towed by the tail? In CT they have a "homebuilt" class for trailers with very few, essential requirements. Also, if the gear span is roughly the same as a boat trailer (which in some cases is true), then stability ought not to be a problem either. Naturally, the fuselage (and ...?) would need to be designed to endure tension and other loads not typically incurred by aircraft.
Seems trivial from an aircraft design perspective, but not so much from an ownership one, maybe.