BYU from G5. You could argue if it was better or not, I thought it was and is, but it definitely separated. BYU basically showcased their brand and fanbase while being Indy.
I do think players liked it, but missed playing in a conference for obvious reasons. You have the conference championship to play for, certain teams you simply hate and want to beat each and every year, and you have structure to your schedule. I liked the Indy move and think it was a positive for many reasons. But, I am all in on Big12 and what it brings.