I'll admit: I wasn't a fan of the hire and said so at the time. Mullen had a losing conference record, wasn't a great recruiter, and didn't show any indication of being an "elite" coach (it's rare when an elite college football coach doesn't have a signature top 15 win in their first 2 seasons). Looking back at most of the college football greats: most showcased some ability to win over a superior team based on coaching and game planning. Saban did, Spurrier did, etc. Mullen, notably, had not--and had an abysmal record against the top 25 to boot.
It was very, very hard for me to get excited about him being able to turn us around. But he did better then expected on the recruiting trail, said all the right things in the offseason, and then surpassed expectations in year 1. Don't get me wrong: some ugly losses and ugly wins in there: but I'll concede that those who said Mullen would have our team better by the end of the year were right. Our offense did better and while our defense wasn't elite: it certainly won us a few games on their own (LSU and MSU) and did their jobs in others (Michigan and f$u games were close affairs at half that turned into blowouts when the offense kept going and the defense did their part to get 3 and outs).
Mullen will need to continue to hit the recruiting trail hard to narrow the talent gap and will need to work his magic on Franks (who, admittedly, showed improvement too). One potential for concern is that most of his QBs aren't truly dual-threat guys: but running QBs who occasionally pass. Tebow and Prescott are about the only two he's coached with truly dual-threat capabilities. In this modern era of college football: guys that can do both are at a premium..but of the two, elite passers who can run are more valuable than elite runners who can occasionally pass. Franks showing more willingness to run the ball opened up our offense to close the season--but as teams scout that in the offseason: the script will be flipped again and he'll need to show more evolution in the passing game. Fortunately, we have some great WRs that have shown the ability to get open--so he'll have the tools needed to get the job done.