I'm 5'7",142 lb, and I can sit just fine on my new Deluxe-maybe not quite flatfooted,but it was on the centerstand ( I bought it yesterday without even riding one!) . I've had a bunch,from a 1980 Sportster that fit me very well, to a '71 Norton Commando that had me on tiptoe at stoplights. None of them were ever too big for me to handle,though.
I did watch some guy on a fully-loaded Goldwing tip over last summer. He was making a very slow-speed turn in the parking lot,and over he went-*clunk*.
Lucky for him,there were a bunch of his co-workers around to help him get it back upright. I do not anticipate this being a problem with the RE