I ride around Packery Channel in Corpus Christi on Padre island. What is good is that there is a boat ramp about 1/2 mile up the channel, right by the surf. There is free camping on the beach with a bunch porta-potties around, and the law enforcement is pretty layed back out there also. There is a nice 1400 sidewalk top jetty for people to go out on and take picts of skis while not get wet doing so. The place is called J.P. Lubey (That name trips me out).
I used to launch on the beach, but now I'm lazy and use the ramp. The action on the beach is non stopped on the weekend, bonfires and parties all most every night. I used to take my NICE 50cc (Chinese honda knock off, lol) out there all the time with no problems. Port Aransas is a bit more structured than Lubey is and I believe the beach is semi blocked off to surf access.
The good thing about packery channel is that you can go cruise the intracoastal waterway with family on your sit down, or hit the surf on the stand up or vice versa. all from one ramp. It has it all and for free. The surfer community stepped up and played a big part is keeping the beaches open to all. Thus keeping out the big resort that was supposed to come here. There are hotels on the island that are not that expensive even in summer (the holiday inn is though).
Oh yea, the local game warden is cool with people doing tricks and such on skis. Just obey the 50ft rule and no wake zones, as I have had a few conversations with him over the last season.