If the existing laws were enforced properly, there would be little need for doing what Florida is doing. I'd point out that the "buffer zones" may well be found illegal as violating the rights of vessels in transit to anchor.
I don't really know what existing laws can be used to solve the problem. Used to be each city had their own laws to solve the issue, which itself was a problem. Now the state has taken over and told the cities "You can't restrict anchoring, we own the water, we'll study the issue" which IMO is the proper thing to do.
I think the idea of allowing cities to setup mooring fields to "restrict" anchoring is a decent concept, if it's done properly. This creates revenue for the city, facilities for people using the site, can be good for tourism and eliminates the "junkyard" effect. So instead of a city posting "you can't anchor here", it forces them to develop the waterway as defined by the state for "proper" use by boaters.
But I worry that the mooring pricing will end up being absurd at some point and people passing through shouldn't be forced into using them by absurd buffer zones.