I can only think of fifteen different kinds of units, not including orbital. Fighter Bomber Gunship Transport Artillery Tank Damage Sponge Gunner...
I think you've got something here. I think that buildings should fall in with the commander. So t1 is your defence and main fighting force and t2 is...
I haven't been able to read the whole thread, so I don't know if this has been suggested already, but I would like to see an internal play-test...
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