I saw the game on nookrium. Thoughts after playing like 7 times with humans. It seems that low tier unit spam is pretty powerful in combat and in early game is the only option you can afford and in mid to late game you have a lot of population space to spare so that tends to be my "choice". Mid tier and higher tiers units i've found they die to easily to lower units spam from the ai so the only profitable answer to that was to build most of my armies with bunch of peasants a wagon and cavalry or cleric since wizards and crossbow were so much more expensive and always had significant loses. idk if that was the intended way to play or not specially since the ai is not develop yet and can't counter any strategies. My balance recommendation would be to make more relevant higher tier unit which seems to be the more fun by making the 1 cost units cost 2 and lowering the price of the other a little bit because for example with peasants and fighters i am paying 3 times more for something that's barely 2 times better so with 2 armies of full peasants i would crush any army that the ai sent that was 3 to 4 times more expensive