The only thing I can think of is vcpu configuration. on a modern windows guest you really want to set it to x86_64_V3 or better. Avoid host without tuning, and QEMU/earlier X86_64 variants can have missing cpu features.
No and propably never will be since they use the same features of the kernel ( namespaces, cgroups etc) and host system ( apparmor etc ) so any update might introduce a breaking change. This is more likely with major upgrades ( like PVE8 to...
I have 580.173 working fine. I dont use the apt packages as nvidia doesnt seem to care about Trixie support, but the NVIDIA*.run installer works without a hitch.