This could be said for any new feature added.
So your idea to have players see more of the world is to create a third city that they'd sit around in? I can't say it's a very long-lasting plan.
When you say that they have a more "sinister or evil" look, are you trying to say that they'd all have angry expressions, or that they'd spontaneously grow horns due to having betrayed their faction? Would each existing race require new customization options?
Do they have to be max level to do this? If not, where would they quest afterwards? Would Azeroth require a whole new revamp?