Sorry, just bumped into Autosport Forum after more than half a year hibernation, but for a start I will answer the CPU question:
Reasonably tasteful case
6 core i5-9600K 3.7 GHZ (Do I actually need an i7?)
Not. At. All.
I've got these specs:
MB: ASUS Z170 Pro Gaming
CPU: 4 core i5-6600T @ 2.7 GHZ /14 nm / max. TDP = 35W
RAM: 16 GB Corsair DDR4 RAM 1066Hz (yes, the slow ones)
GPU: 8GB AMD Sapphire RX-580 Nitro+ (code name 'Polaris' / 14nm)
Storage: 500 GB SSD Samsung 850 Evo 2.5'' (standard SATA-II 600Mb/s interface) - solely dedicated for my Steam sim games (1TB SSD PCI2.0 would've been preferable for me here, since I install lots of mods, too).
PSU: 650W Corsair VS-650
Sound: Onboard with latest RealTek HD Software - either to older Medion 5.1 speakers or through digital-analog converter to historic old 2 x Rotel amplifiers and 4 x 300 W Dali Suite 3.5 loud speakers in oldfashioned BiWire cable setup 
Screen: 27.8'' ASUS VP278QG
Sim-gear: Logitech G27 (more FFB than G29) / or Keyboard 50% of the sim time. Except for this week concentrating on improving on ACC.
Internet: 370Mbit downstream / 75 Mbit upsteam. Ping : 8ms (in online series, always use wired eth connection - NO WiFi whatsoever).
And I'm running AC, ACC, rF2, AMS2 and PC2 fluent in 1980x1080 with almost full details in every sim.
Quite a cheap sim setup and think it must be one of the cheapest competing in ACC CP sessions - but that'll do fine for me 
Edited by stenovitz, 05 July 2020 - 18:02.