I think no matter how it's implemented, formations to place units will make the game too slow. Perhaps it's better to include a "move" formation for all units (even females). When tasked to a point (rather than a target), units will go in that move formation (probably a 16:9 rectangle, as that's a very natural-looking ratio). When they are tasked to a target, that target can be economical (buidling, gathering, ...) and then they don't use a formation (or perhaps check the distance to see if a formation would be useful). And when tasked to attack, I'd keep special formations as an option for certain civilisations / unit types. Then loose units should fight a formation like they fight a building, deal damage to the formation, and the formation should distribute it logically over its members. So perhaps we first need to focus on the "move" formation, make sure that long walks are fluent, and the distinction between targets., before we focus on battle dynamics of a formation.