Party fowl also has a more expansive menu. Hattie B's is still the best though, I would just go there at like 3:30 when there would be a very short line.
I really like spicy food and don't think I'm a wimp, but the medium intensity hot chicken I had at Party Fowl was REALLY fucking hot too. Much hotter than the same level at Hattie B's. If you have 5 heat-levels on your chicken with medium being the second lowest, you should really adjust it so that medium is tolerable to regular people. I swear that stuff was hotter than anything else I've ever had, including lots of ghost pepper flavored products and all the other spicy food I had living in Nashville