The evidence I would site is that there are posts about how hard it is, how easy it is, how great level scaling is, and how horrible the level scaling is.
Only in a game as open as this one could there be so much of a perfect balance of opinions. Clearly, they got it right. If it were too hard, people would fairly universally agree, it's too hard. If it were too easy, again, all the posts would complain that it's too easy. Instead, people are making different decisions as they play the game and finding differing results... just as I would expect from this sort of game. I'm quite pleased with their work and they should be proud
