Sorry I can’t help with the proxmox stuff but it is absolutely fine to have a qcow2 image on an SSD pool. Modern SSD write endurance is so high as to be a non issue especially in the relatively tiny work loads that HA will put on it
This is huge for me as well and is what will keep me on Ubuntu Server until I have a very very good reason to leave or someone else adds it.
Sorry I can’t help with the proxmox stuff but it is absolutely fine to have a qcow2 image on an SSD pool. Modern SSD write endurance is so high as to be a non issue especially in the relatively tiny work loads that HA will put on it