Top 10 isn't a good expectation yet. Maybe in 10 years we'll be a consistent top team in the big 12 and making the playoffs sometimes. But even that would be a dream come true.
BYU doesn't have the advantages to be a top 10 program consistently. We have the foundation set for the future, and we've done amazing with what we've had, but consistent top 25 should be the goal.
Every team in college football has at least one letdown game a season. Only a couple are good enough to still win all of their letdown games. Most team do what BYU did last week every single year.