Balance in Heroes 5.

Dude, I'm not talking about defensive towers and walls, but about the tower that gives you half of your army in the form of level 1 gnomes. And they are, arguably, the most durable and armor-piercing level 1 units. And starting with a Dwarf as the main hero or with a Dwarf as an additional hero (you can also make him the main hero) is a viable option.

Added 1 minute ago
And on a large map, the gnomes will be able to develop normally.