Indy money estimates have been various. It's difficult to draw conclusions with the public data (yes, I've seen ksl).
I think playing multiple P5s each season is "more to play for" than the rare AAC championship game. Bowl games are exhibitions, not regular season games. I think you have this backwards.
On rivals, whatever you gain in continuity contradicts your next point: exposure is much worse. The majority of eyes tuning into ESPN games against P5s are the P5 fanbase. And we've left good impressions on many of them, without repeats, increasing the exposure factor. Why are you thinking it's mostly BYU fans?