I know the feeling of one magical dealer feeling useless in a party. It happened in my first game too when I didn't know what I'm doing most of the time. I thought the same back then too.
But as I played a few more playthroughs, I started really loving the armor system. It made it so that focus fire isn't ALWAYS the best strategy (eg stun 3 enemies instead of killing 1 and stunning 1), took the luck out of fights (there's still crit, but that's as good as it will get; even league of legends still has that), and made weaknesses more apparent. Also, you have the choice between a mixed team that have the best tools for everything you might encounter, or have a focused team that bludgeons the problem away with pure firepower. Adds a certain depths to the game it would otherwise lack, makes replays a LOT more fun, and promotes creative ways to beat tough fights without resorting to cheese.
@Letuce... don't forget the heals+decay combo, which along with the reactive armor is the only way to actually benefit from dumping loads of points into elemental skills while doing physical damage.
