Or how about a modifier key (e.g. Cmd/Super) to make the Touch Bar display global hotkeys rather than local hotkeys? I think it already somewhat does this. But it could also display any applicable Services, which (through making Services in Automator) would cover the macro use-case.
The right-hand side of the Touch Bar is already the "control strip", which is systemwide, and it has a < at the left of the control strip that expands it to the whole Touch Bar. You can even set that to be the default if you don't like the context-specific softkeys and just want the systemwide ones.
