Willow tree, Not anywhere near the beach. Says it all. So not an option for us./ Myrtle Beach State park. No sites close to the ocean, (you have to drive to the beach), and only a few sites with full hookups. Again. Not an option.
Yes The big three have golf carts, and OL does let you bring your own. But for us it is the most crowded, and hardest to get around in, and the sites we have had there are pretty small.
Lakewood is ok. Not so many carts as OL, but larger sites on the beach. Bath houses are old, and no AC.
PirateLand. Our Favorite. HUGE sites on the beach. (not in the trees) Much quieter than the other 2. Much tighter control of the golf carts. And they are required to be on site by 11. No excuses. At OL, and LW. They run all night.
And yes PL DOES allow you to choose your site, as long as you pay for 7 days in advance. You can still cancel, But you can pick your site. they also have a lazy river.
Something else to think about. At the beach. You really don't want to be back in the trees. Trees will burn you up in the summer. They kill the breeze. On the beach. There is always a good ocean breeze.
BTW. Myrtle Beach Travel Park. Is really a good CG, All pull thru, and large sites. Lazy river, and near restaurant row. Plus they only allow their permanent campers to have carts.