spread the woof and help me find a job (oh and a home, too!)

Darby needs a little helping paw to find the right home. He is a cocker mixed with something else, maybe a mini golden retriever? We aren't sure but he sure is cute. Darby was adopted and we discovered that once he gets into a home environment and begins to feel comfortable, he becomes a bit of a challenge and displays some dominant behavior. He needs to find a home with someone who has some solid dog behavior experience or someone who is at least dog savvy and can work with a trainer on Darby's behavior modification. He wants to do what he wants to do and without an experienced handler, he is going to do what he wants and give you a growl if he doesn't want to stop doing it (such as getting into the rose bushes or the garden or getting on the furniture and doesn't want to get down). He did see a dog trainer who suspects that Darby will need some further training and a firm consistent alpha dog guardian. He also needs a lot of exercise and a "job" so that his smart brain can be diverted and put to some good use. Maybe doing agility? Being a running buddy for someone who runs every day? Maybe herding? He is very smart and very active. He may need to be the only dog in the home until he has better training. Is there any hope for Darby to find the right home? Can you help give him an extra boost by emailing his story and pictures around or facebooking it to everyone you know? Thank you so much!