Some are more interesting than standard PC races! I'd replace halflings and gnomes with goblins, for example, in a heartbeat for some campaigns.
It really depends on the campaign, though. And I usually would only allow humanoid, goblinoid or possibly a few monstrous humanoids. I also wouldn't want ECLs much over +2, although I might be talked into a +3 if it made sense in my campaign world.
HOWEVER, I think there are TOO MANY humanoidish races around. For all my campaigns I always trim them down somewhat. No reason to have so many different types of humanoidish races -- it just becomes an illogical patchwork of cultures that are thrown up for convenience, not for any sensible reason. So, I usually limit campaign settings I do to about half a dozen or so humanoid races -- including PC and NPC (monster) races. So, if you keep fantasy staples like the elves, dwarves, halflings, humans and orcs, you don't have room for much more.