In large scale computing, a server will have VERY powerful hardware. You can run multiple VMs on that one machine, giving a slice of that power to each VM so that it basically ends up with multiple individual computers running on one very powerful set of hardware instead of building a ton of individual.

The fall off on ram performance vs cost is to the point where it’s not worth spending extra money. That kit picked out will be good.

You actually have a very solid pc picked out. I’d say the other details needed would be what quality you want to play the games at. You’re likely good with the 6700 xt if you don’t want to max every game and get the 165hz to match the monitor. If you’re not trying to push the envelope while on a budget, I’d feel very good with that part list.