You know.. I always find it about 50% exciting and 50% frustrating.. when you get an unexpected chick or color hehe.
There's that part of you that wants to "know" what your parent stock is and what your chicks are going to be, and it's not usually desirable to find that there are other genes at play to throw out unplanned for results.
But then there's that part of you that says.. "what the hey".. this is unexpected but actually really fun .. because now you are learning. You are really investigating your birds, their genes, the possibilities, and often that random chick turns out to be one we actually really love