I agree with Santa; the timer needs to be increased, at least to 1 minute and 30 seconds per battle.

Instead of the standard army composition with 2 native units, a growth unit, and a meat shield unit from 3 heroes, here you have 1 unit that is usually not native and a growth unit. Essentially, the army is at least twice as weak. With such an army, even simple battles with weak guards are already challenging. I remember on the road, there was just an obelisk guarded by 20+ wolves, which effectively meant 40+ wolves, and the result was a loss.

Developing 3 cities and the possibility of having 112 battles with an opponent also lead to a reduction in the timer.