Good post. One other thing that should be said has to do with the /why/. Why do we design many games like this? There are some obvious reasons: it's easier, it's fun, it plays on our natural reward mechanisms, etc. A perhaps less obvious one: it reflects the world as many /wish it could be/. Straightforward; full of definite, predefined goals; having well known, well understood challenges; having predictable rewards that are trivial to compare to others; having a very linear path for "progression" (via leveling up, attribute increases, etc.) A world with a WHOLE lot less variables.