Why use Landlords?
I usually don't upgrade peasants for a long time; I always use them for income, and I keep about 10 peasants in my army for the units that are sacrificed and absorb retaliatory attacks.

By the way, it might be beneficial not to level up the main hero's "Experienced Commander" skill. Experience suggests that it's not difficult to level up a secondary hero to "Master Counter-Striker" + "Experienced Commander," and it's very advantageous not to have the main hero return at the end of each week for retraining.