- Racials are very unbalanced and are punishing to new players (or players which pick a race because of visuals), by not picking the best race.
- For certain classes (priest for example) one race is better for one spec whilst other is better for others (high elf for smite, dwarf/human for holy for example) this encourages for making multiple characters of 1 class which in most cases is not a realistic option
There are ways this feature could be added without loosing the RPG element.
To begin I would create quests which would allow this. They would require a level 60 and could be scattered throughout the world. Every class would have a quest available from races which can be that class. Quests themselves could be heavily focused towards each of the respective race's cultures and could be focused on a lore friendly way how the player could learn such skills. By completing these quest you could enable a dialogue option with that specific NPC to switch to their respective racials.
As NPC's would be scattered throughout the world, players would need to travel to them in order to swap their unlocked racials. This would also encourage more players to move throughout the world, which I consider a positive.
I would even go as far as allow races of opposing faction to pick racials of their counter parts, IF the race has that class option. Cooperation between factions is part of the lore so this could be accomplished.
Here is a simplified example of what one of these quests could look like:
Dwarf: NPC would be located somewhere on an icy mountain (maybe near Ironforge or in Alterac)
To learn the way of the dwarves player would need to procure certain ingredients to create specially strong brew (this could be a combination of getting Greater Stoneshield Potions, traveling to Grim Guzzler to buy some alcohol, finding some ingredients in treasure ... ).
Upon returning player would be sent to Ironforge where they would seek someone who could brew this concoction and return to the quest giver after. With the brews procured player would need to drink all of them and get completely hammered to build resistance to alcohol, whilst also turning to stoneform.