When I hear ideas like this, it feels like the hobby will never escape the unthinking fear from the 80s. Ugh.
I don't play evil characters myself, but I feel strongly that the ideas have to be there so that it's a player choice -- that the system support the all available choices. As long as alignment is presented as a character choice, all available choices must be supported fully. I'm fine without anti-paladins, frankly -- it's not that all choices need to be identical, and alignment-specific classes are (IMO) fine -- but of the options available, there has to be full support.