Which Haven heroes do you prefer?

I'd like to see how you'd deal with 80 monks on week 6 by simply overwhelming them with numbers (and knights usually train light, so you can't avoid damaging them)... I'm probably not talking about games on week 55.

Your favorite monks are actually healers. With proper management, taking them down like archers is easy. And it's not just about dark magic, as you think. That is, sooner or later, they will have to switch to melee combat. But even here, they don't shine – with their damage, units of level 4 are unlikely to drastically change the course of the battle, even though they don't have a penalty in melee combat, or you will be casting your light spells. Their only advantage is that they are tough and it will take a long time to kill them.
P.S. But not longer than it takes to kill paladins, who pose a much more serious threat.