To be honesty I would not worry about identifying breed that much. Breeds are just a human construct, to enable things such as rabbit shows to operate. When it comes to pet rabbits, temperament genes are the most important. The kind of tenement that makes a good pet is not really judged at rabbit shows (ok, being "laid-back" enough to tolerate handling and being able to pose are in a way judged).
If the rabbit makes a good pet that is all that matters. It can be fun to look at a bunny and pick out the characteristics in a mixed-breed bunnies sort of like looking at clouds and imagining what they look like. I am saying just don't take it TOO SERIOUSLY.