Being independent offers scheduling flexibility and makes it easier to get games against top teams since the Big 10, Big 12, ACC, and SEC all consider BYU a P5 for scheduling purposes:
http://www.cougarboard.com/board/message.html?id=15055308
You wouldn't get that in the MWC. Further, BYU has a larger fan base, higher attendance, and stronger tradition than all G5 programs (by a good margin) and about 1/3rd of P5 programs (including Utah). BYU would be ranked 3rd or 4th in the Big 12 in both attendance and academics (#2 in basketball attendance). This team obviously belongs in a P5 conference. So, we can build our own program or go back and try to help Wyoming, Nevada, San Jose State, etc. build theirs. Why? So we can win their trophy? No thanks!
I'm happy with independence until Oklahoma and/or Texas leave the Big 12 and we can consider joining what's left.