I quite like the idea of the [man://...]
and [man://program (1)]
I'm not sure about [man1://] - it's quite intuitive, but it goes against the current design of having one pseudo-protocol per link type. So I'd rather go with [man://program (1)] instead (but don't really mind either way).
As for the mskb links: I've never posted a link to one of them (but then again I don't use Windows either), and haven't seen particularly many here in posts or in the Chatterbox. But I don't think they would do any harm either, so I'm not against it either.