He looks to be a mixed breed rooster. At 5 months, what you see is pretty much what you get, they don't change a lot color-wise at this point, just fill out more.
He has some barred ancestry, but the pattern is such that I don't think he he had a purebred bird as a parent, it would have to have been further back than first generation.
i agree that he has disorganized feathers but i bet that this rooster will grow up 1x time more than normal barred rock