I left out an important one in my previous post.
The way ‘classes’ (professions) and ‘races’ (species) interact would be much more like Basic D&D (where non-human races are their own class, so that for example a character can be a 4th level Halfling), than 3rd and 4th editlon (where every race can be any class, so that you can have Halfling Sorcerers).
Actually this is true if D&D was based on emulating fantasy fiction whether old or new.
It seems to me that having open class/race possibilities is based on extrapolating what a fantasy world would actually be like. If, for example, there are magician’s guilds and halfling villages in the same world, does it make sense that no halfling has ever become a magician? No. Therefore there should be halfling wizards.
Whereas having ‘racial classes’, or at least very heavy restrictions on race/class combinations, is more like how fantasy fiction usually works. In Lord of the Rings (although this isn’t that clear in the text and is only made clear by what Tolkien said) ‘wizard’ isn’t a profession, but a species. The wizards are meant to be Istari, basically a type of angel.
Are there any non-human wizards in the Harry Potter series? There didn’t seem to be in the movie I saw, but I’m not sure if that’s true in the books as well.
Actually even humans would probably be divided into ‘races’, or more accurately ‘cultures based on an imagined cycle of barbarism to civilisation to decadence, and then perhaps divided by class’. Conan, the Gray Mouser and Elric’s natures all seem to be very tied up in the fact that they’re from barbaric, civilised and decadent societies respectively. Sir Whomever didn’t choose to become a knight, he was born to be one.
Likewise in Lord of the Rings, ‘Ranger’ is a race, or perhaps the upper class males of a race (are there meant to be peasants who feed the Rangers that do the actual patrolling and craftsmen who make their weapons and armour, or does the whole population live off the land? I don’t actually know)