It's a matter of perspective. My first thought when reading the docs was, "All someone needs to do is slap a GUI on this baby. Good thing the designers made a simple CLI that it could interface with."
They've already done most of the heavy lifting. At this point a GUI is trivial to add. "Terminal–first" doesn't imply "terminal-only". In fact, quite the opposite. I wouldn't be so quick to assume that they don't envision a GUI at some point-- Why not contribute to the project and get the ball rolling?
The patch command [0] has a propose subcommand that describes what you're talking about. It generates a patch from a commit (on any branch, I presume). This can be applied however you see fit. And the checkout subcommand even lets you generate branches from patches similar to GH. What seems to be missing?
