Tyler Do'Urden
Soap Maker
I guess I am a bit old-skool in some regards... but I think one of the problems is players feeling that they can "insist" upon such things in the first place.
Just because a race appears with a level-adjustment (or a silly monster-class progression) in some book somewhere does not mean that a DM is required to let you play it.
Asking is fine of course. But the player needs to have a VERY solid back-story and character concept to make it worthwhile. And even then I would veto the idea if it was completely out-of-place in the campaign I was running.
Yes, this. Back when I ran 2nd edition AD&D in high school, I had a player who would show up at the game with some piece of complete cheese (like the Complete Humanoid's Handbook, or Faiths and Avatars, or both) and insist that he had to play a Minotaur Specialty Priest of Mystra or some such nonsense. Then, when I'd say no, he'd pout and say that I had no right to do that, it was part of D&D and therefore he could use it, he'd take his dice and go home, etc. It was really, really annoying.
What made it all the more annoying was that, using the Player's Option series and Michael Morris's "Dusk" materials (which were then hosted on TSR's website), I'd built a very elaborate (and often unbalanced) system of character customization which should have been sufficient to keep any creative player busy for years.
You just can't please some people.
Now, 3e's racial classes and ELs were an innovation I really, really liked. But I always placed restrictions on using them to prevent cantina-scene scenarios. Nobody complained- I think it was a matter of increased maturity...