Is there a way for us to make sure the text sixe on both the primary output screen and the foldback screen are MAXIMIZED so that the words on each slide of text is as large as possible? In EW2009, I know the song, in general, would make the words as large as the slide which had the most text on it. Is it possible for there to be a slide specific setting which will maximize the text so that it is as large as possible?

Not that I can tell. EW6 has same automatic sizing logic where it shrinks to fit rather than expand to fit. Earlier versions of EW6 had a maximum font size for songs but latest version no longer has it. It was confusing program logic to auto-size with maximum size and trying to shrink to fit. You'll have to manually set font size if you want largest size; if there are multiple slides make changes to slide with most words before applying to entire song.