I don't hate the idea but I don't support it either. This path is very broad and personal so it would be hard to form a council to represent all witches. Personally we represent all witches because some people might meet you and the way you present yourself will be how they think of witches from then on.
On the other hand if this council is suppose to lord over witches, pass laws, create a code of ethics and basically tell us right from wrong it's useless as we are responsible for our actions. Being able to say 'well the high council witch said I could' really takes a key element out of witchcraft in my opinion and kind of tarnished my path. I'm my own moral compass, I rule my actions, my reward/punishment is given to me by a higher power [deity, karma, universe, whatever] and is not the result of mortals choosing for me.
Overall, don't need one, we are to vast in our views it would be hard to make everyone happy.