Cavaliers kick arse. Their biggest bonus is probably the resistances (20% resistance to fire and acid, immunity to poison). In addition to all of the normal paladin powers they absolutely rule. I prefer not to have my cavalier memorize healing spells because my cleric will already handle that end of things. I prefer the offensive spells such as Doom, Holy Smite, etc. and the defensive spells such as Bless, Chant, Negative Plane Protection, etc. A paladin is, IMO, possibly the best tank there is because of three simple words: Shiny Plate Mail. Carsomyr is a nice touch to a Cavalier but hardly necessary. There are plenty of single handed swords that will handle the situation at hand in addition to having a shield which will give you nice AC bonuses and also any other effects that a given shield may have apply. Any way you look at it, a cavalier is a force to be reckoned with. And the whole paladin background is cool too. How can you not have a grand ol' time as a nigh unstoppable force of holy retribution?
-Jafin