RangerWickett
Legend
No, it isn't.
PCs and Monsters playing by the same rules makes for a consistent and believable world. Something that many people value.
Having them play by different rules means that, like in 4E, the PCs are "aliens" who can never do what the "locals" do, even trivial stuff while possessing powers of their own no one else has.
And I leave that to Sci-Fi games.
I think you misrepresent what we want. We'd love PCs to be able to potentially access any power or ability or combination thereof. And if the game doesn't have rules published yet to handle them, there should be some guideline for GMs to add them. Exception based design cuts both ways; the published rules are just guide posts for you to balance other options around.
But monsters? Monsters are supposed to be scary. A hero who knows how many hit points a troll has and who is wholly prepared and confident in his statistical success is not a hero. A hero is someone who goes into a dark cave to save a kidnapped child, and who doesn't complain when a serpent made of shards of glass rises up and attacks. He has no idea what it can do, how he can kill it, or if he's going to die.
And that's awesome. To me, at least.