First thing that comes to mind is dogwood tree, altho they can be fickle and not sure if you are too far south. There is another tree that is supposed to be like the dogwood, I am thinking silverbell???but could be mistaken and not sure if it takes sun or shade.
Another choice would be azaleas, they do love the south, and typically do well under pines and like acidity which the pine needles provide some. Azaleas can get pretty big if you let them, and they have the Encore ones now, which I don't have experience with but hear they flower more. Also camellias, which I love, and find easy to grow, as an added bonus they are evergreen and bloom in fall/winter.

Thanks so much for your response. I was thinking camellias and azaleas but wasn't sure if there is enough sun, especially for the camellias. Didn't even think about a dogwood, we have a few in the front, but I don't think they are thick enough for hiding the roadway and neighbor's house. I have a holly out front that gets almost no sun. Do you think I could take cuttings from that? How long would it take for a holly to get 6-7' tall from a cutting?

Well I don't know too much about hollies but I do have a few they seem very slow growing and I understand they like more sun.
I have grown camellias from cuttings and they became 3 to 4 feet in a year or two in Louisiana.

Japanese privet hedge. You should be able to dig them from the wild almost anywhere in NW Florida. They should be evergreen in your area except for that winter once every 20 years when you get a hard freeze. Prune them once a year, wider at the bottom and they will fill out nicely.

How about a native to your area ... saw palmetto with scrub palmetto planted in front. It will fill in, give a tropical look and grows under pine shade all over Florida. Saw palmetto grows about 6-8 ft tall and the scrub palmetto stays fairly low to fill in under it.