Andrew, an important topic that coaches like me spend a surprising amount of time working on with speakers. Getting the introduction right means that a speaker is properly built up for that particular audience. The speaker then has credibility before starting and doesn’t have to brag about herself.
I particularly appreciate your point about avoiding humor. I’ve seen far too many VPs of Marketing try to tell a silly story about spilling something on the tie of the presenter, or something equally trivial, and get lost in their own cleverness rather than put the focus on the speaker, where it belongs.
One further tip: a presenter should shake the hand of the speaker after the intro as the speaker is moving to the stage. That helps ground the speaker, and makes a visual connection with the speaker for the audience.
And one last thought. We often write and produce video introductions for speakers precisely to control the uncertainty that all too often means a bad introduction, despite all the effort expended.
The Speech of Introduction - Boundless