I’m pretty impressed by KC 576. It appears to be easily modified to make it handicap accessible. It would have worked on our building site – but is oriented wrong for the views. (We have nice views that are something my in-laws enjoy). And there’s no space for stacked laundry or other “niceties” that make a home more livable.
I notice most of these take advantage of an open living space (living/kitchen flow together) – that makes a HUGE difference in a small house.