I think it would be worth modifying the game... (re-uploading)
Adding the missing factions (because we only have these, since the others didn't play a significant role in the plot)
And also, we could add: Swamp, Dungeon, Sanctuary (and Island Orcs)

+ It would be good to add alternative units (e.g., swordsman/pikeman) and a 4th upgrade (expensive and powerful)
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In general, I have many ideas... I won't tell you everything...

Added 1 minute ago
+ We should also add bosses and new campaigns...