Rawls’s book was at the center of my Master’s Thesis (1988). I have thought many times since then, too, about his “original position.” I think he did the best job possible of justifying some form of redistribution on the grounds that people should only be ‘better off’ if everyone is first of all ‘well enough’ off.
As it happens, I discovered a way to accomplish that goal without having to redistribute anything: “For Crying Out Loud, ACCEPT That A SOLUTION Actually EXISTS” (a “2 min read” — including options for further reading — here in Medium).