bigger and better football, basketball, and track stadiums; far better baseball, softball, and soccer fields; and better practice facilities. Ok St has a nicer golf course and tennis facilities.
Now I'm not saying OK St has amazing facilities, but their Athletic Dept is pretty comparable to BYU's. They are a mid-tier P5 program, and BYU beats them in most areas. In fact, I think BYU's overall facilities would rank 3rd in the Big 12.
BYU isn't Alabama, but it compares well against most P5 schools.