Three thoughts:
1) At least a third of those concept helmets are a gorgeous improvement over existing designs. I love, in particular, Browns, Chargers, Cowboys, Dolphins, and Rams. The most disappointing are Colts, Giants, Seahawks, and Vikings. Oilers don't count as they don't exist. Yes it's all subjective, those are just mine.
2) I never understood the Bill's red "side bumper" going across the blue buffalo silhouette. If it's meant to suggest "zoom" or speed, well, it's painfully simple.
3) In Denver's, the exhaled snort graphic coming out of the horse's nostril at a sharp angle from the natural downward direction of the horse's head looks odd. If you look at it, it looks like a Dr. Seuss-drawn character sticking his finger in the horse's nostril.