Upgrading issues - stability, usb drives and documentation

Unfortunately I've found the combination of Parallels 16 and Big Sur disappointing with a Mac VM: I have a litany of problems that I've waster a lot of time exploring a lot of different settings. I have a reasonably powerful Macbook Pro (16GB RAM, i7 processor, 1TB disk, 2017 model). Problems I've had

• laggy performance on the upgraded Mac VM, sometimes on the laptop monitor and sometimes on the external monitor
• freezing for a few seconds on a mouse click or some other action
• USB drives not appearing in the VM
• VM crashes or Finder crashes when trying to browse the external drive

There's lots of discussion in the forums and so on, but none of really says how things should be configured. It's often written for a Windows perspective - and I run those too, but it's the connection to my Mac VM that's the problem. The documentation might say what to do on the VM side - but often doesn't say anything about what has to be configured on the host side. It's certainly not been as easy as the documentation suggests!
I wish I'd waited a few more versions of Big Sur, Parallels. They often sort these kind of things out.