The only reason small dogs are possibly "more bitey" than big dogs, is that owners of small dogs usually don't really address the biting, because they're not causing any harm anyway. Whereas the owner of a big dog knows that the dog could really cause damage if they wanted, so they work to stop the biting. And then, of course, there are the retrievers who have soft mouths anyway, and if they do bite, it's usually not hard at all.
Just be sure to be very consistent about the biting - with my chihuahua, any time I feel teeth on my skin I get up and leave. Even if she just accidently brushes me, that's too bad, I'm gone. Now she usually catches herself even before I can get up, if she feels that she touched me she'll go ahead and go to bed until I come back!