Having five masters of coin roaming a map and firing off at different times doesn’t really amp up the concern level. One creates tension, makes you have to plan around things. “Oh, we need to handle this!” Half a dozen is just flat out annoying and makes the game play drag. Perhaps simply up-powering the zombie horde that hits the well a bit would be a better option when there is already 1 type of that boss roaming the map.
Also, the leveling of armies and heroes feels a bit off.
I can take a horde of Goblin Savages ( 6 power each with 60 members = 360 power ) stick them to defend a fortress with an inn-keeper and you’ve easily got a 1k unit. Do the same thing with the dwarven king that starts at 400 and you have a 410 power unit. I feel like a percentage boost as opposed to a flat +1 would feel better, and more thematic, and interesting, would be if the troops had different tags they gained through battle. ( And not just these wimpy I went after a single zombie and killed him so now all my troops get +1 power battles. ) Also, archers,artillery, and the like should be able to gain some XP for doing their job from afar.
After a certain amount of experience maybe instead of just a simple +1 they gain a tag that grant bonuses, and are perhaps limited to different unit types, for maximum flavor. Things like…
Fleet footed/Swift/the Quick - units move faster
the Brutal - Units are 10% more powerful
Elusive - unit can bypass zombie hordes ( as if flying. )
Veteran/Battle Hardened - Units get a +20% saving throw
Glorious - Units receive 50% more valor from combat
the Brave - cannot be targeted by fear compulsions
Skilled/Experienced/Wise - cool down on power is reduced by 25%
Champion/Hero/Expert - Applies a 5% bonus to troops fighting with him
Eagle Eye - range distance is increased by 25%
the Holy - cannot be killed in a battle in which their side wins.
These are just some random power ideas, but I feel as though it would add a lot more flavor and make the individual troops a lot more interesting, because then we could have things like
Elusive Elven Archers, The Holy Cyclops Priest, Skilled Artillery, The Brutal Dwarven King, The wise Forest Dryad, Battle Hardened Human Swordsmen, Glorious Veteran Knights, etc.
which would just be cool and make each of the units in the game a bit more unique and add flavor, and make leveling up your guys a bit more fun.