I have some more ideas about nerfing some building bonuses to stop from overpowered late game units. BTW it's kinda long:
Armory- +1 armour
Barracks -15% unit cost, +15% unit replenishment
Proving Grounds- +3 charge
Master Bowmaker- +15 accuracy
Mountain Hermatage- +1 xp for monk agent, +2 xp for bow, naginata, matchlock, and naginata cav. monks
Fortified Monastary- +1 xp monk agent, +3 xp bow, naginata, matchlock, and naginata cav.
Pilgrim Hostel- +2 xp monk agent, 1xp bow naginata, matchlock, cavalry; +1 morale
Great Shrine- +2 xp monk agent, +1 xp all warror monk units, +3 morale
Pirate Lair- tariff trade income +15%, +2 xp sailors
Pirate Fortress- tariff trade income +30%, +4 xp sailors
Warehouse- tariff trade income +30%, +1 xp sailors
Red Seal Company- tariff trade income +60%, +2 xp sailors
Master Weaponsmith- +3 melee
Armorer- +1 armor samurai, ashigaru, and warrior monk
Master Armorer- +2 armor, samurai, ashigaru, and warrior monk
Just some suggestion, but it makes the gap bewtween well trained and supplied units a little less than before. Combine this with your lowered xp bonuses and the balance should be better
Also, I will be heavily modding units stat for better balance when the PFM is done. I will probably create a submod for TROM.