Alignment penalties? Do we have alignments? :O I only remember them from AD&D and going against them was not too good, especially for clerics of palas.
The total disregard for alignment restrictions is one of several problems with this workaround. There should be penalties, not XP, for most PCs to kill most NPCs. It is completely inconsistent with the allowed behavior of characters in pnp, and mechanically it has created problems for an already messy quest system. This spell should be implemented in a way that does not make it easier to violate the spirit of your character's alignment just so you can min/max for more xp or items. That would never be permitted in pnp. Killing innocent or friendly NPCs should always have dire consequences for your character, that can't be fixed by casting this spell.