Oh yea, there is also the Courtney Campbell Causeway. There is also a public beach right next to the Clearwater Sailing Center that people can launch sailboats from.

I think you can legally launch a non-motorized watercraft from any public beach in the county, but there are few that you can get your boat trailer close enough to (I could be very wrong in this assumption though.) I'm not sure if the same rules apply in other Florida counties.

I just checked out this (https://public.myfwc.com/LE/boatramp/public/) Many of the boat ramps listed seem to be for non-motorized or limited horsepower watercraft.