Acme Lowcountry Kitchen or Seabiscuit Cafe for Breakfast. The Obstinate Daughter on Sullivans Island is a nice dinner place. Home Team BBQ on SI good for lunch. The Wreck in Mt. Pleasant good hole in the wall seafood place. Waters Edge, Tavern and Table and Nico(French) are good also.
Jestine's, Callie's Biscuit, Husk, Hominy Grill, Oak and Halls downtown are good. Marina Variety store for breakfast. Some just off the top of my head.
I was sorta disappointed with Acme. I was on Isle for a few days and i must have hit the wrong spots other than that place with the roof tiny roof patio at sunset that was awesome.