For now I have ballooning off as when I installed last year it would give OPNsense more than 2GB, but I believe this is solved now and just something I need to get around to checking out again.
I am not sure if I should use Ballooning or not, when the guest is running Proxmox reports around 90% RAM usage, when in reality is no more than 20%, I have been playing around with Ballooning ON/OFF, but it doesn't seem to solve the memory reporting issue in Proxmox, are you experiencing the same problem? Thanks
Unless things have changed recently you have to use q35 for successful pci passthrough, balloning still is unusable for freeBSD and yes to qemu agent. Needs installation inside the VM too.