Have walkway construction work more akin to conveyor construction. Choose a starting point & ending point.
Walkways will snap to valid snap points.
A 4-way intersection that has railings on all 4 sides, but intelligently removes those railings as walkways get connected to them. These serve as the start and end point if a walkway doesn't snap to something more specific.
Add snap points to the bottoms, sides, and top of the walkway intersections to attach conveyor belts, with appropriate visual attachments when conveyor belts are attached.
Maybe add the ability to attach power lines to them in some fashion even? Now that I stop and think about it... why can't we attach 2 wires (just enough to continue a line of power) to conveyor poles...?