Further to the first question in my post, if anyone does actually know of a way of making text “expand” like I describe, I am also wondering if there is any way to do it WITHIN a word.
For example: the word “Thanks” would appear on screen as a subtitle and then expand outwards to “Thaaaaaaanks” as the word is drawn out in the speech of the video itself. To be fair though, that almost certainly would involve an entirely different set of animating techniques, so this is presumably just a long shot to ask that.