No. they aren't. They are the focal point around which the game, in a mechanical sense, revolves. No matter what their background, history, or purpose, the game is, ultimately, about the PCs, not the NPCs. Detailed options that are available to them on a regular basis are superfluous or extraneous when applied to NPCs who are only going to be on-screen for a limited amount of time, and powers and abilities that might be exciting and engaging in a limited quantity (such as the hypothetical encounter with the shaman who can heal and sling fire with equal ease) will prove problematic in the hands of people who are on-screen all the time and have those abilities as a normal part of their problem-solving repertoire.