ve now had the system running for a couple of weeks now.
The GPU is ITX sized RX570 - so its small - allowing extra space for air to flow. Im also pumping a lot of air in from bottom front Noctua 140mm fan.
The only real gaming we have used it for is Fortnite and F1 but CPU is hitting low 50s and GPU low 60s.
The exhaust fans are top may help you ??
PS Ive only got stock AMD Wraith Stealth CPU cooler. Again, small and not causing much air flow impedence.