I agree that there are some great restaurants but we probably disagree on the ones we consider great. It really depends what you want.
If you want quality places like Grill 225, Peninsula Grill, Oak Steakhouse, Magnolias, Hominy Grill, FIG, Jestine's Kitchen and Cypress are very good. You will find more Lowcountry cooking at these places.
Places like A.W. Shucks, Hymans, Gilligans, Bubba Gump and Charleston Crab House are more of the tourist variety. Basic seafood but not Lowcountry cooking. They are good for what they are but if you want more of a local flavor I would go elsewhere.
IOP does not have quality restaurants but there are some places to go. Mt. Pleasant has some good choices as well. Try the Boulevard Diner on Coleman Boulevard.
IOP and Sullivans do not have major hotels but you should not have a problem finding a condo or rental home. Folly is great but be advised that it has "character." Most of the homes are older and it is a bit run down. There is not as much to do around Folly though if you want to stay in a hotel the Holiday Inn is decent.