Few points.

North jetty is a big surf spot when the fronts push a north wind/swell. Not a good place to launch in those conditions. I think it's a state park, so you may have to check about launching there.

South Jetty is clean on the north swell, and not bad on "usual" days. Access used to be limited, a sandy spot right next to a condo building, but they may have built that out since my days windsurfing there.

There is a public park along the south side of the inlet (Mapquest says it's Seaway Drive, and the photo shows a boat ramp, too!) where you may be able to park and launch. Currents in/out of the inlet may be up to 3 kts, but should be manageable if there is any breeze.

And I don't think there's any reason you couldn't launch from the intracoastal and sail out...