My problem keeping the system ASRock build running was, in hindsight, always BIOS related. I wanted the improvements other BIOS version supposedly introduced for NVMe support and memory compatibility and the microcode upgrades for the CPU to address both compatibility reason and address CPU security.
My secondary system was seamless with one exception. It did not correctly identify the amount of memory available to the embedded HD530 video controller until I added the correct platform ID into the Devices section of clover.