OK, I just read that post four times.... it was interesting.
First time through, I did it with something I imagine an older, lady British librarian (not saying Tez is a librarian so leave that be) saying it, which was rather soothing.
Then with a sort of Paris Hilton (remember the way she talked?) voice in my head ... that was disturbing.
And then worse of all, with a sort of Kim Kardashian vacuous vocal treatment.
And then I did it with Rocky Balboa. Bam! Perfect. For the soliliquiy not for Tez's voice, so let that be again.
The reading of text-based communication from another person to oneself in the privacy of one's own mind is an interesting experiment in personal security vs egoism, I've found.
The reality is actually Judi Dench as M, accent and career fits. Occasionally Maggie Smith as the Dowager from Downton Abbey.