Illumination and the hexgrain problem

[triangular_cube]

Its difficult to visualize without actually seeing it, but I believe you tackled this in a limited approach on the 2 hex units (USN Destroyers on the Gavutu map as an example) with a hexgrain toggle on the unit itself. The all encompassing hexgrain toggle does seem like a cleaner approach than one on each and every overlay/unit/whatever. 

My point is to consider adding those 2 hex units to the design on the hexgrain toggle.