Originally Posted by DArtagnan 
Don't let the players choose - because the players aren't artists. They're players.
With that I'll agree 100%.
Ultimately every design decision should be taken for a reason by the person who "knows" - even these art films are so uncomfortable and challenging because if you lack the ability to understand them their meaning will be lost with you or misunderstood.
I'll just point out that although the designers should not let the players get design decisions they should still take the 'particularities' of the ones they choose as their audience into account.
Also… I can't resist:
Originally Posted by DArtagnan 
Like Oblivion, where everything scales and the "difficulty" is completely superficial and rigidly simple.
Man… don't bring Oblivion into this… This aspect of Oblivion is absolutely bloody terrible, it doesn't even worth to be mentioned as an example of an exception.