As far as blowouts go, it has happened in the BCS era with Miami/Nebraska, Southern Cal/Oklahoma, whoever played Notre Dame, Florida/Ohio State, and pretty sure I am forgetting others. In the CFP era, Oregon/Florida State, Alabama/Michigan State, Clemson/Oklahoma, Clemson/Ohio State, Alabama/Washington, LSU/Oklahoma, etc.
I think the 12 team playoff will give us some good/great first round games. And hell, if there are blowouts in the first round or the natty, or whatever, we can't blame the 12 team playoff because blowouts have already happened.