Thanks @concordnz / @SpartanVXL.

I understand smaller SSDs are slower for write, but 2700MBps write / 5000MBps read is plenty for me. The read speed is about the same as the larger SSD. That disk is mostly for the OS / programs which really don't need super high performance, and uses 70GB max for me. If I get 256GB SSD I'll partition it for 128GB for the OS, 128GB for random data like caches which is what the video editing program uses when you're interactively using it, so it'll be fast. My video files live on a RAID0 mirror of spinning disks, and if I move them my project files won't work if I open them later.

Yes buying a very fast CPU, faster than I need, just for future proofing - if I start doing more development, docker, VMs, etc. I understand cooling and mesh cases can help performance when the computer is busy, but reducing noise is more important to me than absolute speed as the only time it will go to full CPU for more than a few seconds is batch jobs which I tend to run while I'm doing something else. I'll just put good fans in and turn them up when required.

I'll wait and see with RAM. If it costs $100 for faster RAM that might help in the future that's fine. If it costs double and gives me 5% then I'll get 3600 or whatever makes sense.

Maybe it makes more sense to get a cheaper Intel 10500 or similar based system - thing is it's half the speed (but still plenty fast enough) and the full system is only $400 cheaper, which is why I figured Ryzen was a better option. I just like the idea of AMD / Ryzen and I tend to buy the newest range - I waited six months already for Zen3 and can wait a few more months as I think my old PC will be fine for a while longer.

What's the better brand of motherboard Spartan? I find Gigabyte reliable.