Paladins... Probably the most interesting class to play and yet because no one can agree on any one archetype being the most correct. People are often viewed as playing them wrong.
1st point of contention: Lawful Good; that's Lawful Good, not lawful stupid. I've seen far more of the latter than the former. Just because you play someone who has faith in an ideal or in a God's superiority, doesn't mean you ignore the other gods or the fact that those with differing ideals can't be useful to you or your goals. (Baring working with the 'Evil' that falls more under the purview of Chaotic Good - At any cost let the result that leans most towards benevolence win etc.
2nd point of contention: "It's easy to lose your class abilities." Yes it is, but rather than look at that from a directly mechanic's point of view, let's look at it from a role playing point of view. How awesome would it be to start a game (or join one,) with a character who's a Paladin who's working towards atonement. The amount of Story lines and adventure arc's. Hell it could very well drive the party through some things that most wouldn't consider otherwise.
Also side note: Superman's OK, but the true paladin in my eyes is totally Steve Rogers