By south do you mean south south like Carrabelle, Crawfordville, Wakulla and St Marks? Or east and then south like Perry?
If you mean Perry then Goodman's BBQ is one of the best of not the best in the state and its maybe a third the price of 4 Rivers in Tally. And oddly enough considering the town is the most redneck of any decent size towns/small cities in Tallahassee outside of the Okeechobee area, the best Italian place in all of North Florida is Mama's in Perry. The best seafood in the area is Deal's Oyster Bar which is low rent but the best oyster bar outside of Apalachicola, Cedar Key and Panama City that I've found. No decent steak that I'm aware of as I believe Chaparalls is permanently closed.
If you mean the coastal area south of Tally, then Hammanknockers is the best in the area although their only really good item imo is the bbq smoked wings. Their ribs are just ok and their other meats are below Sonnys level but their smoked wings are usually exceptional. There's not amazing seafood until you hit Apalachicola where there's a ton of amazing places (Boss Oyster is my fave), but there's a lot of decent to good places all around Crawfordille to St Marks and over to Carrabelle like Ouzts Too, Poseys, Tropical Trader Shrimp Company, Angelos, Spring Creek, and Seineyard. As far as steak...I'm not aware of any steak places in the area either but Im not looking for it on the coast. I would say that I believe Wakulla Lodge has steaks to go with really great prime rib and fried chicken but I've only has the prime rib and chicken.