This might be helped if there was an app on the Macs (or Windows) that allows you to download before departure certain tags or classes of cards.

Let me add a slight twist to this. Allow for main content to be only saved locally not internet connected. But allow to collect online activity, but be imported to offline via easy to integrate with offline brain. Allow for same analysis of off-line/local data without having to push to the cloud. This is a liability, actual control, intellectual property, trade mark, copy right, and privacy concerns for certain industries and individuals.

Agreed, some form of caching or offline mode, to be able to read previously synced notes