free airtime

is an excellent idea, Vernon, I agree.

It's worth noting that the Fair Elections Now Act in Congress includes public funding in the form of media vouchers for candidates, so that those opting into the voluntary system can run a robust campaign and get their message out on broadcast TV and radio -- as well as hire staff, run a field and communications operation, etc.  Certainly the ability to get fair exposure through media buys is critical to a campaign and therefore critical for comprehensive public financing.  You can read more about it here.