Which Orc hero do you prefer?

Why is that??? The probability seems to be 1/3... Or am I mistaken?

Because they won't guarantee the racial perk, as it already exists.
Therefore, they will offer 2 perks from the machines to choose from.

And Garun can also be used against the Haven faction. Their attack stacks are rather weak, and they usually rush forward. Dryads, Dancers. And even Archers aren't that tough... You can quickly build up an attack.
I, for example, in a 3*3 Duel, used a Garun (I created the preset myself) and reached an attack of 100+ with Cyclops by the end of the battle. +21 attack for each hero killed - it's fun :)