Patterson should be nowhere near any hotseat for TCU. Gotta be patient, TCU isn't a powerhouse that can win 9+ games every year through key players graduating. They needed a few years to rebuild and develop a new core, which is what these last 2 seasons have been. Looks like they finally found their QB, that's huge for their future. Their goal should just be to win 6-7 games and make it to another bowl with a freshman QB.
As for the defense, it's pretty much impossible to field a dominant defense in the Big XII. What you saw against Texas may be as good as it gets...force key turnovers to make up for the yards and points given up. OU and Texas have better talent on defense and still get torched so yeah, it's just part of being in this conference.