In Timber Turncoat, it seems like the number of scouts that spawn is dependent upon the cost of the unit you use to defend. For example, with archers, there are many scouts:
While with griffin riders, there are few:
Is this intentional, or a bug?
The extraCode of the referee is very scary (ok, not really but still):
Seems to be more likely to spawn a scout when there are more than 7 healthy fighters, in addition to the wave.
For every n healthy unit greater than 7 units, there is a (n/2) percent chance of spawning an extra scout.
Extra code like this is very common in levels, though this one unintentionally backfires.
More often than not the level scales with the Heros MaxHealth. Other options to scale with are range and damage. I can only assume that the intention in this level was to scale with the army-strength. While we could only summon soldiers and archers the relation number of friends ~ strength of army was true (more or less). But now we have way more units to choose from. It probably would be better to scale by army-cost (as estimate for strength). Difficult topic, this balancing.
As with all things this game changes, and perfectly balanced levels become horribly unbalanced, sometimes simply because a behaviour changes. When Sotonin introduced that fire-traps trigger nearby fire-traps on explosion some old levels had to be reviewed. When the changes to the palisades occurred multiple levels broke completely.
Keep in mind that the levels are often designed and balanced to take place at a certain point in the campaign, in order to highlight something for the person who is learning things for the first time.
We generally won’t try to balance all the levels for future gear, except for multiplayer or repeatable levels. It’s somewhat intended that players will go back and exact bloody vengeance on earlier levels that used to be difficult, but are now trivial with their shiny new sword 
As for Timber Turncoat (and Timber Guard) yes, the idea was to spawn more scouts if you managed to summon a ton of soldiers, to smooth out the randomness so that the level didn’t feel boring if you got lucky and had an overwhelming force of soldiers surviving because of the timing of the random ogre spawns.
Even after removing all my armor, sword and shield I still can’t pass this level, because my summoned soldiers die too quickly.
I wish I had those griffins already!
