Give Chuck Robinson a call (he’s in the Nashville book). He is only one of a small handful of men and women with an FFF masters certification–he is the former owner of the FlyChucker. He is about $40/hr and worth every penny of it. If he is unavailable , then try Steve Nix at Fly South.
An hour or two a with a certified instructor, or at least someone who is a serious student of casting principles, will improve your skills dramatically.
Gary and Wanda Taylor are also master certified, but live near the Hiwassee. You might be able to book a trip with them (assuming they still have time for it) and get some excellent casting instruction, and invaluable fishing tips as well. Plus, the Hi is an absolutely beautiful river to float and fish.