Granted, as far as class design goes, protection paladins are sitting fairly pretty (and not just the blood elves). Our rotation is great, our stat priorities produce a fun playstyle, our talents do what they need to. We don't have any serious holes in our stable of cooldowns, and on the whole staying alive isn't really an issue for us as long as there's a healer nearby. If you had to ask me what the biggest source of frustration with my paladin is, I would quickly reply with the inconsistencies of how aggro plays out.
That's not to say that single-target, Patchwerk-like aggro is an issue. Vengeance as-is means that tanks really aren't going to lose threat if they have a lead and they're being punched in the face. Rather, where the look and feel of the system breaks down is on the periphery, and in particular when new adds appear as the clock ticks on those crucial few seconds between spawning and gnawing of the closest healer.