Admittedly it would be nice to have origin twists to the mage class. I wonder if they had explored any race origins for the mage before the final cuts before the launch.
In the tower Duncan asks you if it's been difficult being an elf, and yes the conversation with the elf is slightly different, but otherwise it's the same, as far as I remember.
Most peolpe will treat you as if you were a city elf. Never played a human mage, but my elf mage seems to be recognized as an elf WAY more often than as a mage.
So if you have already played a city elf (or plan to do so): Don't bother with another mage run just to be an elf. You'll hardly see any reactions you don't know already.
You will occasionally get elf-specific dialogue options, and occasionally mage-specific. Often people's first reaction to you will be about your being an elf.
Only Difference would be your shorter pointy ears and everyone hates you twice as hard as they hate Human mages ... but meh you can set them on fire for thier insolence