Since clearly 1984 was the high water mark of the program, I'm going to start calculations beginning with 1985 to see what the program has been since then.

Lavell from 1985-2000 averaged 8.7 wins per year
Crowton from 2001-2004 averaged 6.5 wins per year
Bronco from 2005-2014 averaged 9.0 wins per year

Since foof chose a five year average in his "BYU has averaged 5 losses per year" stat, I'll do the same. The following are rolling five year averages of the number of wins BYU has had beginning with the period from 2010-2014 and ending with the period from 1985-1989. So, LaVell years are on the right, Bronco years are on the left:

8.2, 8.8, 9.2, 9.8, 10.0, 9.8, 8.6, 7.4, 6.2, 6.4, 6.4, 7.0, 8.0, 8.2, 8.6, 8.8, 9.2, 8.6, 9.0, 7.8, 8.4, 8.4, 9.0, 9.2, 9.2, 9.4

The average of those averages is 8.4.

The BYU program of the past 5 years looks an awful lot like the BYU program of the past 30 years - with ups and downs from all the coaches we've had in that period. Of course, you and yours will call acknowledging this being "complacent" or "settling". Can "we" do better? On an "any given year" basis, absolutely. On a consistent basis? History says maybe, but don't bet your life savings on it.