Since mapping out a rail path is so easy now I would like the FARL to follow the ghost path of rails placing all that is needed and stop at the end of the ghost path.

That sounds like a very nice idea. Back in 0.11 (or 0.12?) i toyed around with making FARL drive to a destination on it's own. Was a bit messy since i had to do the pathing myself.
I think a first simple version could be: hop in the farl, ghost blueprint the tracks, start and only drive forward. More advanced: create a railpath, turn FARL into automode, go do something else while it builds the track xD

I think a first simple version could be: hop in the farl, ghost blueprint the tracks, start and only drive forward. More advanced: create a railpath, turn FARL into automode, go do something else while it builds the track xD

Did anything ever come to fruition here? Can FARL be set in maintenance mode on an existing track and follow it around and replacing the rails behind it self? Auto replace layout so to speak?

It can follow ghost rails and place the layout. Maintenance mode doesn't work (yet).