The single biggest factor for UU recruiting now is winning. The MW had its limits but the BCS appearances in the NFL track record helped time.
The Pac-12 help quite a bit but when you to struggle, it hurt. Now with all of those factors in play, UU is doing very well. About as well as can be expected. But winning is crucial
I suspect the same will be for BYU. A natural bump with recruiting friendly coaches and the excitement of a new conference.
But long-term, I think winning at the higher level will be key.