Of course it is derivative. But they are not the same elves that you find in D&D. Elves in the Warhammer world are not the nice, goody-good-two-shoes tree huggers that you find in D&D.
And the druchii are far apart from the drow. There is not much in common between them beyond the fact that they are "evil" (evil being a relative term in WFRP).
Even if the elves are derivatives of Tolkien, they are changed enough that they are intressting, and only partially the generic elf.
It is mostly the history of the elves, and just a part of it (the short thing about them leaving the mainland, and some stayed behind), that is derivative from Tolkien. The rest, such as culture, they have more in common with Moorcock´s Melnibonéans. Especially the High elves and the druchii.
In fact, if you check the warhammer history (the game, not the world), Melnibonéan miniatures was available for WFB, but then they got an angry M. Moorcock on their tail, and the minis quickly was renamed Dark elves.
The point is, you said that gloranthan elves would be a shock to most players because "they are the enemy". And that is what I commented about. If you have played WFRP long enough, you will not be surprised that elves are "the enemy" or are capable of performing evil deeds.
In fact, only MERP, LoTR RPG, and D&D are the only games where I can really say that elves are truly good, and are fully following the archetype set down by Tolkien. There are probably more games, but those were those I can remember at the moment.
It can even be argued that the Gloranthan elves in their visual style are derivative of Tolkiens works, since the elves of folklore and mythology does not look anything remotely like Gloranthan elves. And the only "original" about them, is that they are plants (which in some cases seem to affect how they look, and sometimes it does not).
And another point is that the looks of elves does not have to be what makes them unique or original. Just as humans it is their culture, their religion, and their mindset that mostly makes them original or not (though it can also be argued that no fantasy race is original since it is only an aspect of a human culture or the human psyche).
Which brings me to another point. Namely suspension-of-disbelief and the ability of a player to relate to the character he is playing. By definition (so far) a player is a human being, and we human beings relate more easily with beings that looks like us humans, works like us humans, or are some aspect of us humans.
As such fantasy races by definition becomes an aspect of a human culture or a part of the human psyche. We most easily relate to these creatures if they meet our expectations of how the aspect they are part of should look.
For example, orcs most often are warlike, brutish, and stupid. Is it then a coincidence that we portray orcs as muscular, hairy, strong, and somewhat primitive in their appearance?
This is basically why I think my players (and probably others) discard races that simply are made to look "different" for the sake of being original.
Think for a while if you would manage to role-play a dolphin, a dog, a carrot, any plant, and relate to that character as much as if you were playing a human character, or a near-human character.
And now I wrote a much longer post than I had intended. I never intended this thread to explode in such a fashion as it has done. I just wanted to know if the elves and dwarves were of the generic or the bizarre sort...