I think Bevell deserves a lot of credit. Most teams that run read-option in the NFL commit to it fairly strictly (SF with Kaepernick, Carolina, Washington, etc), and the offenses they run are very obviously dumbed down. Late in the season I thought Bevell did an awesome job of mixing read option with a traditional offense. The result was a whole lot of games over 400 or even 500 total yards. People talk about playcalling/predictability but that is just one aspect of what an OC brings to a team. How that OC fits the existing talent is what is most important, and Bevell fits it perfectly. And for the record, I think Bevell's playcalling is just fine. Most of the crying over his playcalling comes in brutal losses where the offense did it's job and the defense didn't, and MMQB'ing takes over.
Sure, Wilson made Bevell and not the other way around, but I'm fine with that. At the end of the day Bevell may not be the greatest OC in the game, but he fits Wilson as well as anyone would. If Andy Reid or Jon Gruden came in to run our offense, I don't think it would be a whole lot better, simply because Wilson and Bevell seem to have developed chemistry working together.