I never particularly cared about belt optimization past 'good enough'. I spent most of my time trying to break things and find edge-cases in the control system. Working around the (purposefully nerfed to keep them from being too powerful) logistics bots issues was probably my favorite thing to tackle.
(That, and building vast quantities of artillery in the middle of almost fully red zones, then flipping the power switch for the loaders and watching the fun. :D)