re: This game cements it.

I get where you are trying to go.. you can have a great team with a better offense than defense, but that is the exception more than the rule. When it comes to having a championship caliber team, you need to be above average in every facet of the game, no doubt. However, think of it this way. The point of it all is to score points. Offense scores points (and prevent points if it controls the time of possession which your examples weren't designed to do). Defense can prevent points, score points by themselves (pick six/fumble return), and give the ball back to their offense to score points.

In my opinion, playing great defense has more value. Obviously, having an efficient offense enhances that. But if your offense has a bad day, you can possibly score points with a great defense and deny the opponent a scoring opportunity. Great offense and poor defense just means your opponent has equal opportunity to keep pace with you.