So, let's assume BYU is without Mika next year.
We have the following post players:

Andrus
Dastrup
Childs
Worthington
Shaw
Nixon - not sure he has the size to play the 4 but he's not really quick enough to play the 3. Maybe stretch 4??
Seljaas - as a stretch 4

Am I missing anybody? Not terribly impressive. Is this enough? I think we need another PF. Dastrup, Andrus, and Childs would have to hold down the 5. Then mix and match at the 4