Oh yeah, NVMe is an absolute given. It only took one NVMe drive experience and I have never had a desktop or laptop since without a large NVMe SSD as the boot and primary disk. It is in many cases a substantial boost and you can benefit across more things than a bigger CPU since many things these days are IO bound to begin with!
I’m rocking a Samsung 970 Pro 512 GB on my desktop. I never thought I’d need more space than that, since I can always use my NAS or the spare spinning disk I have installed. But, the more CPU power you have, the more you can feed it... I find myself building entire fragments of Nixpkgs now and it takes substantial disk space to do it.
I would think the extra cpu would be more of an impact with Rust than even C++... I wouldn't know, running a 3600 as a place holder until the 3950X comes out. I couldn't handle the 4790K anymore, going from 32gb to 64gb and the couple extra cores made a huge difference for my docker/vm workflows. Can't wait for the 3950x. I'm sure the TR 3rd gen will be similarly impressive with the changes to IO.