Yes, the Anti Paladin kit is certainly overpowered. The Dispel Magic on hit is too powerful for SoA. To add insult to injury, i actually dualled my Anti Paladin to a Mage... And at level 13!
I also noted that keeping an unenchanted Katana took the "Improved" out of the "Improved Mages", so i decided not to use it. In the Tactics Mod, every creature and his sister can cast Pro-Magic-Weapons, which nullifies my Dispel Magic on hit. I can risk by casting my innate Dispel Magic, but that would wipe my buffs, too, etc...
However, since evil is
really discriminated against in BG2, things balanced out eventually.
Personally, i feel that the Anti Paladin is an
incentive for people who wants to play evil in BG2, and not just out of roleplaying reasons. Don't you agree?