well, I dont think we need to maximize distribution of elements.
I see two factions, and the goal here is to represent those factions, but trying to fit a card into each element doesnt really do that. Each faction has certain attributes, and those attributes are embodied by certain elements. So instead of taking the factions, and linking them to each element, its taking the factions and extracting the core of their attributes and the elements that represent them. I dont like the idea of trying to 'fill a grid' so each element has a card for each faction. Its about a war between two factions, of technologists, who have a varied sense of the world and want control of certain resources, differing on how they would use them.
I see about 16-20 cards, 8 to 10 for each faction, that represents that faction. I dont think we need one for each element, its superfluous. Its not that they wouldnt use one or the other, you can tie most anything to anything else if you try hard enough, but its about the embodiment of the faction, the aspects of them that are most visible.
Gaian
Above ground forest dwellers. users of biology and life sciences. Users of transmutation and avoidance, guerrilla fighters who hit and run.
Probably has
walking trees
an air force
hybrids
ability to change abilities or traits in battle
gas clouds
venoms and poisons
Cthonic
Under ground dwellers, users of mechanical technology and chemistry. Users of reinforcement and hard defense, direct fighters who rely on force.
Probably has
tanks
tunneling equipment
machines that crush
explosives
missiles
ability to strengthen in battle
I actually would like to avoid 'one of every flavor' here. Id like to see elements used as activation costs over card type.