Alternative:
Run 2 polls. One for the current Council members, plus any newcomers to it, whowant to take a chance, out of which the top 8 gets a spot. The remaining applicants are gathered in another poll for those who have never been in Council, where 4 members come from.
I'm just brainstorming here. It's pretty simple to me, though; some members of the current Council will be highly unlikely to get a vote from me. Fresh blood is the way to go.