[contextfree]

In principle there could be voice shortcuts; currently there seems to be an expectation that voice interfaces should be entirely limited to natural language words and sentences, but if we're willing to let this constraint go (at least for "power user shortcuts") and just design bespoke syllables in IPA or whatever, we could probably come up with something more efficient.

It also ought to be possible to specifically design interleaved voice+keyboard, voice+mouse, voice+touch, voice+pen, etc. interactions that could be more expressive and efficient than either input method by itself.