Yes they start with 0.
I don't necessarily think 30 people will create them, nor do I think it's unreasonable for there to be more overall players in the league than there currently are. If it gets unreasonable, add a team, but I don't think it will.
Perhaps they could be limited to one season post-cap (where they can't add anything) and then are auto-retired and have to make a new one. It might not be perfectly fleshed out but the skeleton of an idea is here.