I have a few suggestions: 1) make the upgrades more tree-based, instead of tier-based. it doesn't really make sense for my Lancer to upgrade to a Priest, then go to a Grey Knight, that just doesn't really make sense. 2) have the different mission types be more unique. it kinda feels like theres just 3 types: Point A to Point B; Kill Everything; and Escort the Caravan. My third suggestion is that you can buy already leveled-up Soldiers. like if you say "hmm, I think I need another archer, maybe I should lose this second knight", you should be able to get an archer the same level as your other soldiers.
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