So replacing the stock pads with some fujipolys might be an expensive option to better control vrm temps.
Could be specially if you/someone owns a damn good z370 and worries about running 9900k through it. Naturally good airflow /case would help as well.
Had my z370 gigabyte itx hitting 116c when benching, alphacool 17 kwm pads at £50 a pop and dropped to 80c... Though exhaust and top fan was near it as heatsink was VERY hot to touch
EK GPU blocks ship with 3kwm pads, most people don’t change those blue turds. Personally I would suggest Gelid Extreme pads as you can get those for about £7 for 80x80mm, thermal performance close to the Fuji pads at 12kwm for a lot less cash and good enough for the job in hand.