No on/off switch on the display? Must be a pretty basic controller if you can start it w/o the display connected. Some of them need certain wires connected. How would you shut down the motor if it took off on you? That could happen if the ground wire on your throttle breaks. At least one brake switch is handy.

Anyway, for the wires you're not using, It might be a good idea to write down the wire colors and keep the connectors, so you can re-use those accessories if you ever change your mind.

Don't cut with baterry connected. I done that once. Kapow.