If you are ever in Charleston check out the Aiken-Rhett House. I thought they did an excellent job of talking about slavery. (All of the house tours we saw acknowledged it, but most still focused on how fancy the houses were, without really talking about who made them so fancy.)
McLeod Plantation on James Island, SC, also does an excellent job of keeping the slave economy central. Amazingly, some of the slave quarters were still inhabited as ~1980, which itself is stunning (no running water, etc.).
