I predict you will really appreciate the more practical functionality of the X-S20 controls, especially the Fn dial and the four Custom settings options. You will also appreciate the deeper more functional grip, (no added heavy grips necessary).
After going from the X-T2 to the X-S10, I really can't see myself ever going back to the "traditional" controls of the X-T50 or a any X--Tx camera for that matter. I shoot primarily in Aperture mode with Auto ISO, so the Shutter and ISO dials of the X-Tx cameras are essential decorative for my use. I admit that the X-Txx and X-Tx bodies are more attractive looking than the X-Sxx, bodies, but I'm looking for a photography tool in a camera body, not a fashion accessory with less useful controls.
I'm just going to say it. Fujifilm goofed when they put the Film simulation dial on the X-T50. It should have been a Function (Fn), dial that could have done all that the Film Sim dial does and so much more. Anyone who owns an X--S10/20 knows what I'm talking about.