For sure there is a need for separated design developer role, that actually exists in a growing number of projects. Also I'd separate all frontend developers that do backend work on frontend in a separate category. A growing category because every day more and more responsibilities are shifted to the frontend. Filtering data? Why not on the frontend. Combining data? Frontend sounds like a good place. DB management? Frontend can handle it. Sometimes It makes you wonder what cloud and backend is for 🙂