Not just wire, but multiple circuits using the same block. Since colored wire is going to be available you could have a trunk line that carries four separate circuits. Two opposite sides of the block transfer all the EU along the trunk line, and each of the remaining sides has a separate color (ex red, blue, green, yellow) Attach red wire to the red side at one point of the trunk, and red to the red side further down the trunk for a dedicated point to point circuit. Activate doors and pistons near each other remotely from a control room while taking up 1/4 of the space for wiring. Set generators in remote locations and dedicate power to specific operations while operating several doors from a single switch using the same trunk wire.
Or, have the ability for super advanced machines in the future that are 3-phase. Red/blue/yellow are 'hot' wires and green is a ground wire. Green has to be attached to an iron block surrounded by dirt on three sides and each of the other colors has to be powered by a separate power source. This could also be a way of making HV. Hv could be 3-phase and has to go into a transformer (four inputs to one low voltage output) before it can be used in low voltage machines.
Could be built like:
B Ru R
Bu Ru G = 6 Cables
Y Ru B
B=black wire, Bu=blue wire, Ru=rubber, Y=yellow wire, G=green wire
Place the block and then right-click on one side to set the output. This way you're not limited to them only working vertical or horizontal.