> flashing lights at either side of the crossway
787 wingspan is 200ft (60m). Planes don't turn on a dime either, but the larger ones do have steering linked to the rear wheels, so their turn radius can be surprising.
The non invasive solution would be to require some kind of ground control computer link that can directly draw their controlled path for them on their displays and give them a nice loud master caution or warning if they're about to break their assignment.
Then we can start thinking about ground autopilot systems.