threadripper,
64gb ram 3600 c18 (gaming and since infinity fabric in amd processors don't benefit from speeds higher than 3600)
or 64gb ram 2666 ecc (workstation),
graphic card wait next gen since current gen very boring,
samsung pro nvme ssd for OS and application, buy more than one to setup raid 0 for shits and giggles,
xfp/sfp/sfp+ nic as long as 10Gb/s, a good SAN setup for long term storage with 10Gb/s connection to pc,
cooling just put pc inside aircon room 24/7 can, custom water cooling loop also can, but custom water loop need to be maintained regularly

other parts like mobo, casing and psu as long as reliable (read reviews) and up to spec just pick what design you like, not going to matter a lot unless you're planning to break world record in overclocking

for monitors I personally own an LG 27GL850, but ultrawides and/or semi-profesional series like dell ultrasharp series also interesting

keyboards nowadays plenty of choices, even with custom keycaps and layouts accessible on to buy from internet

mouse is the one thing I'm not sure of, manufacturers say rated to last for 10 million clicks, but after a few months already start double clicking