Cases are very subjective in terms of how you priorities aesthetics vs temperature and noise, but I would say that this will run very hot; this case has pretty poor airflow, plus having a very hot CPU on an air cooler. Remember that air coolers use the air already inside the case to cool the CPU, so as the air gets heated up inside the case from the CPU and GPU the cooling becomes less efficient. Low air turnover inside the case means it heats up more.
For that reason if you do go with a 9900KS I'd strongly recommend a 360mm radiator, the TDP on that thing is insane. Honestly I'd stick with a 9900KF if you're set on Intel. If you're willing to spend that much money on a CPU you need to be willing to spend a lot on cooling if needed.
I'm not sure that the Z390 boards can use Gen 4 PCIe, I was under the impression that it was a new feature on only x570 (AMD) boards at the moment, but I could be wrong. Either way I wouldn't go for Gen 4 SSDs as they run much hotter, are less stable at high temperatures and you genuinely will not notice the difference in speed; storage drives almost never actually reach full speed for any significant length of time. Crystalmark benchmark max speeds do not translate well into real world performance.
I'm glad to see you dropped the Samsung QVO from your initial list, they have significantly shorter lifespans than the EVOs (QLC in general is worse than TLC) which is one of the trade-offs to make them cheaper.
One other thing I would say is remember to save some budget for a monitor. Your PC might be generating 50000 FPS but if your monitor is a 1080p 60hz old wreck you'll miss out on 99% of the benefits of the new PC.
Happy to give a few basic points on that front or direct you towards some youtubers with a lot more knowledge than myself.
Whatever parts you end up using, good luck and enjoy it!
