I have thought about one use that wouldn't overly interest me:
PV - if I do someday own a railcar, I want a nice sleeper and open area with large windows.
This is sadly one thing the Amfleets lack. I know Amtrak experiment with a sleeper room at least once, but I can't see much interest in PV hands.
Now, one thing that Amtrak can do (and perhaps should) is something like
https://planetags.com/