That said, ignoring paladin shenanigans for now the huecava is hardly exceptional, especially with its narrow range of viable classes. Clerics and druids don't want to lose spell levels (and clerics want to keep their domains, too), paladins don't want to fall, and monks are, well, monks. The template may not have been designed with evil paladins in mind, but it sure works better for them than for any other class.
Monks may be monks, but the point remain that the template does a lot for them.
A buff to their main stat. Natural armor. And a damage reduction thats going to be a pain to deal with.

Because im certainly not buying the idea of NPC's with silver weapon.
Not on anything but recurring enemies.
Normal opponents should go "skeleton!" and try to get hammer.

So LA +2