Is ram that expensive? Sheesh, I'm glad that I have bought 32gb of ram while it was cheaper.
Kocytean Gigabyte X570 Aorus Master Motherboard - $629.00
Isn't that motherboard cheaper? I found it on amazon for $360.
Kocytean ADATA XPG8200 Pro M.2 SSD 2tb - $459.00
That seems overkill and unpractical. I'd have 1tb SATA SSD and other 1tb as PCIe or nvme. Also, check if your mobo supports PCIe or nvme.
That seems to be interesting, but their software is ram hungry and...
...how you will use it under linux?
Also, after few months of use your mobo might start screaming about CPU fans.
Kocytean Noctua AF-S12B 120mm case fans x6 - $150.00
Are you really need that much of airflow? I even not sure if your case can fit that much of fans after installing water cooling.