Man, what a waste of wire!
I'd set one 'daughter panel' next to the current 'parent'.
Next, run 20 Amp 277 circuits in groups ( #8 wire? ) towards Lighting Contactor Panels at each of the desired spots.
Look at some of the Tork line, for example.
Control the lights from some point of convenience with low voltage ( 120V or 28V ) relays switching them.
You can use off the shelf systems (Tork) or build up your own ( SqD/ Cutler-Hammer, etc. electrically or mechanically held contactors) or...
You've got too many options to discuss in one post.
