Bar none, the happiest group of graduate students I ever worked with (at a hospital, or not) were the PAs. The education is focused, fulfilling, demanding without being exhausting. The pay is great (I know a number of guys who did a path of: high school flunkout -> GED -> nurse -> PA). Furthermore (at least 15 years ago), they don't have to deal with the vast majority of the insurance BS... they basically get to help & heal.