Разделяй и властвуй

Strong neutral armies are placed in the garrisons so that the main hero can level up, explore everything in their territory, and then move on to the enemies. Between the garrisons, there is terrain filled with interesting things.

Ah, I understand. In principle, yes, garrisons with neutrals can be created, but as far as I understand, the neutrals in the garrisons won't grow in numbers every week, and if the player reaches a certain garrison after leveling up in other places, the army in the garrison might turn out to be too weak for them.
In general, I make the initial development difficult on my maps, even without garrisons, when there are not enough resources and it is difficult to break through anywhere, especially when playing on the "hero" difficulty.