Everything about heroes.

I'll start by saying that the amount of money and experience in chests isn't very different: if there are 500 experience points, the alternative is 525 gold, so you can't get much more gold. Regarding the 300+ latniks: it's usually very difficult to find such strong neutral creatures. There are often not enough resources, but resources arrive every day, while experience can be hard to come by. I take money if there is none, if I can't take experience, and if the amount of money is MUCH (twice as much or more) than the amount of experience.
By the way, artifact merchants trade in not very useful artifacts, and the prices are exorbitant (you can't buy anything good for 9000).

I didn't understand this.

Haven't you ever noticed that all the heroes (except for the campaign heroes) don't have faces? They either have a bandage covering their face, or they just have one face (for Barbarians and Rangers).