This looks great though. +1 choosing Qt instead of Electron. -1 for Python though. Otherwise, your approach ticks most of my boxes.

One feature I'd like to see though is reverse file associations - basically associate Linux filetypes inside the Windows VM so that any file you open in a Windows app would open the file in Linux, assuming Linux has a file association for it. Say I've installed Directory Opus in the VM and I want to use it as my primary file manager in Linux, and say I double-click on a .xml file, I would like to open it in the Linux app associated with that filetype (which would be Kate in my case).

The OCI approach should mean that resources are not ringfenced and held separate from the host, which would be beneficial for applications run on the host. A winapps approach using a VM that is run on the host would constrain the host while the VM is running, which the VM would need to be to make sure the windows app is "always available".

Is there a noticeable performance benefit to using winpodx compared to winapps? How does the idle resource usage compare too?

Can we take this to mean that GPU passthrough is planned? This would be huge especially for running Adobe/Canva software.