Well for me personally, the appeal of playing against type is in roleplay, not mechanics. I want the world to penalize my character for trying to break out of typical racial boxes, not the system.
Also on topic ...
I would like to ask: Why?
I mean why do you want to play lets say "unusual" Class/Race combination? O_o
I would presume its that special characters are appealing ... but then:
![[Linked Image from memegenerator.net]](https://memegenerator.net/img/instances/56560813/if-everybody-is-special-nobody-is.jpg)
Ah, but you see, everyone isn't special. YOU are. You and your group of 3-6 allies are. You're going to meet all sorts of other, regular npcs all the time.