In the future include things involving workflow. Gaming PC? Encoding? Mix?

Right off the bat grab 2 x 16GB Samsung B-Die Team Dark Pro c4 3200 kits. Dirt cheap and screaming overclocking with minimal effort, good for all work flows :p

Is PCIE 4 of value for you, eg faster SSD speeds? If no, Crosshair VII, if yes, Crosshair VIII.

Since 1500 is excessive for Mobo/CPU/ram on and platform, I'll just answer 3950x.

That ram will be 260 for 32 GB, board 350ish, CPU 720ish. In under 1500ez with best you can buy parts. The balance can buy the RGB version of the ram if you prefer that.