As you look at this, please consider thinking about having every troop have:
Race, Troop Type, City
As more cities and troops get added, this would allow easier planning on how a troop fits in. Having lower bonuses, but more possible combinations, would help adjust other troops to be in line with Goblins. One of the reasons they are an outlier is that they are all the same troop type from the same city, while other troop combinations struggle to gather similar bonuses.
The current system also forces some strange choices, like Goblin Rocket being a construct, Goblin Shaman being a Marauder, Priestess being Divine.
So troops:
Brian the Lucky Human Knight Zaejin
Paladin Human Knight Whitehelm
Dwarf Lord Dwarf Knight Khaziel
Grave Knight Undead Knight Ghulvania
Luther Human Knight Broken Spire
Modify the race, troop type, and city bonus to lower values. So 4xknight might get +4 armor.
So Goblins would be something like: (types adjusted for example purposes)
Goblin Shaman Goblin Shaman Zaejin
Goblin Goblin Marauder Zaejin
Goblin Rocket Goblin Construct Zaejin
Goblin King Goblin ?Leader? Zaejin
Hobgoblin Goblin Rogue Zaejin
Boar Rider Goblin Knight Zaejin
This would allow other Goblin Cities to be added, where the goblin bonus is kept. It allows a bonus for Goblins, allows the bonus for being from the same city, yet shows diversity of rolls the goblins play in the city. So it allows Boar Rider to go out and join a band of fellow Knights, and get the Knight bonus.