A situation which isn't unique in the game. And even were it desireable, there are mechanics which can remedy this should Blizzard have wanted to.
And yet, as I said, powerful, undispellable, raid-wide, persistent buffs aren't unknown in this game, at this level, in this Xpac. Some class buffs are dispellable, others are not.Even if you were to design completely different aura effects, they would be difficult to balance because of the first issue I stated: they are raid-wide and persist through death. If they were powerful enough to be an impact on raid performance, it would make paladins a 'required' class. If not, then we'd be in the same situation: the aura effects would be trivial, and you wouldn't particularly care one way or another which was up.
Blizzard COULD have kept an iconic mechanic many associate with the class. They chose not to. Blessings - a button thats pressed once an hour - are hardly more interesting or dynamic and the flaws you point out already exist in buffs provided by other classes.
EJL