Interesting point about "first 15 minutes" - the service (and CLI) we're building will probably guide users into the CLI experience during that first ... maybe first 30-60 minutes, rather than 15, but _really_ early on as they get familiar with it.

From a UX standpoint, that discoverability you describe with the GUI is really about the affordances the user can discern with from the baseline state. That is, the 'rotate' button is visible without the user having to do any discovery at all, it's just _there_. What would the CLI equivalent be - I think part of it is the autocompletion scripts that bash/zsh let programs drop in to the `completions` directory so `command <TAB>` shows you all the possible next steps...? Worth thinking about.