the lost art of textboxes

I can agree with most of this. In lieu of (good) voice acting, I think it's important to make the text as expressive as possible. Timing and rhythm and all that is extremely important, but -- especially if there's a lot of it -- spending that much time customizing each line to satisfaction can certainly be deemed a waste.

I also think it's important to not interrupt the flow of the dialogue with a prompt after each line. This can obviously pose problems, as seen in Double Fine's Costume Quest. The dialogue simply moved too fast, often leaving players punch line-less. Some people just read slower or faster than others, making purely-textual rhythm and emphasis hard to properly time.