A 780 is not going to bottleneck a Ryzen cpu. A bottle neck is more like when I had my 7950 and my Phenom one at 2.3ghz. The cpu could not keep up with the gpu that is a bottle neck. Once I upgraded to my 4690K the 7950 could hang with it just fine.
My cpu in terms of IPC is right around a 2600/2600X (I am oc to 4.ghz) and my 1080ti does not bottleneck the cpu.
If you do get ryzen get faster ram than 2133. Ryzen loves faster ram. Some discusson on that
https://www.reddit.com/r/Amd/comment...sweetspot_for/
Edit I also say 16gb as well. 32 is overkill for what you are doing.