Increasing reading time for each slide on a Storyline project.

I don't think many users would click the pause button. This is only a guess, but I would assume most users would see a storyline course as a weird looking powerpoint. So they would not consider trying to pause even if there was a play bar running at the bottom.

Where I work we do tent to add a simple button so the user has to press "next" before the text leaves the slide or what ever it has to do, to allow slower readers the opportunity to read at their own pace.