I don't have much else to add to what has already been discussed. I stayed at Oscar Sherer in Nov. We stayed in a pull through on the West loop. It was a little tight for my double slide TT. I had made the reservation when I owned my smaller trailer. We made it work but the slide was right up against the bushes. I was in spot P104.
We really enjoyed Casey Key Fish House. Another good place to eat is A Taste of Germany, on Midnight Pass road in Siesta Key. Great food. Try one of their Rum cakes.
I think there's more to do at Mayakka than at Oscar Sherer. We stayed at both. We picked O.S because we wanted to be closer in town. Mayakka is a bit further East of 75.
If you are into classic cars, go visit the Sarasota classic car museum. I've been there twice and it's still enjoyable. Have not done Ringling Museum, but wife did on one of her trips. Marie Selby Botannical Gardens is really cool too. Been there a couple of times, and takes quite some time to go through and enjoy, but worth it.
You'll have no problem finding anything you need within a short distance of the park. It's kinda cool that it's in the middle of town, but still gives you a feeling of somewhat secluded.
Mike