Hexmaps are confusing and forever brand a game as grognard fodder. This is Received Wisdom in marketing. Everyone knows how squares work, though, because of chess and checkers.

C4 is modifiable enough that I believe some enterprising group of nerds is working on a hexgrid conversion, but don't hold your fucking breath, as that's some nontrivial changing. I'm still holding out for my Alpha Centauri full conversion, dammit*

*except there's no way to implement the Unit Design Workshop, waaah