are there upsides/downfalls to single-axle TT's?

Double axles usually have more cargo capacity. Our Dart has a max of 6k and is 5k or so wet, with a cargo weight of 2k.. Most single axles I’ve seen are under 1k.
Handling should not be a problem if set up correctly.
Tipping over w/ a flat is not a real concern if on relatively flat ground. Limping along w/ a flat might be.
I would think that a 7’ width would eliminate a walk around queen.
Can’t really think of an advantage except maybe cost of tires.