It occurred to me (after all these years) that the destination runway transition for a given STAR should be given to you at the start of the STAR from Center. So for example:
Center: "Delta 121 is cleared to descend via the Eagul Five arrival, runway 26 transition."
OR more generally
Center: "Delta 121 is cleared to descend via the Eagul Five arrival, landing to the west."
You correctly have approach control clearing you for a given runway at the last waypoint but the pilot should know the runway transition at the start of the STAR. Of course winds can change while you're on the STAR and the runway transition can too, but that is usually something that you would get in real time from Center or Approach control.
Center: "Delta 121 continue via the Eagul Five arrival, now landing to the east."
Of course, if there you're on a STAR that is completely wrong for the new runway I don't think there is much PF3 can do since you can't change the STAR in real time. But in real life you can be pulled off the STAR and given vectors at any point then PF3 would have to know for what runways a given STAR is valid as part of the flight plan setup. Maybe a user designated checkbox on a STAR waypoints preceding the runway transition waypoint where PF3 checks the winds one final time?
I don't know if any of the above is even possible, but figured I'd mention it anyway since its Friday and you obviously have nothing better to do than listen to us PF3 users ask for stuff.

Regards,
Mike T.