It’s been a while since you posted this, but I wanted to add something to the first part, about not repeatedly downloading the same torizon OS base image/tarball over and over again. I’ve previously suggested (here: Torizoncore-builder: Caching a auto-downloaded base image ) that tcb can be configured to use a local file if available, and only downloading the tarball if no local image is available. If that would be implemented, and you could configure your CI/CD environment to cache the downloaded tarball between builds, it would be downloaded only once and then the cached copy would be used for subsequent builds.
