AE GPU acceleration is Ray tracing and Nvidia only. It however is rarely used by most since it's limited to certain processes. CPU and Ram are far more important for AE performance and C4D. The only time you get GPU acceleration from C4D is on render with 3rd party GPU acceleration plugins/renderer such as Octane. If you don't get those then the CPU threading and Ram are the most important aspects for C4D. Premiere will definitely use the GPU with the MPE engine however it's far better with Cuda than Open CL right now. So Nvidia is what you want. The 780Ti card has far better specs and far outperforms the Quadro K4000 by a sizable margin. The only benefit to the Quadro is 10bit color preview if you don't have an I/O card. The Geforce with an I/O card though is still a better option if you do need 10bit color preview.
Eric
ADK