games that allow you to decide whether to trek through the Desert of Certain Doom or the Forest of Inevitable Demise has spoiled us a bit -- we expect to have a choice.
MMOs are hardly exempt, and in some ways even worse off, with players who want to choose which quests they do, which abilities they learn, and what their character likes in a pie. Of course, by the same token, it's better to have one path that's fleshed-out and interesting than a half-dozen with hardly any expansion to them, whether it's a path to the level cap or just a chain of learning abilities.
So the question is, how important is the power of choice? When leveling, would you prefer variety of zones without as much quality to each area, or a full dint of quality in far fewer different places? Do you want your characters to learn anything even if there's not much to learn, or do you prefer a single path that has been expertly balanced?