Good Post. Atleast in the PC version, the defensive AI is an important factor in you running offensive plays against it. I don't look so much technically at the game as in "what program flaws can I exploit?" That is simply no fun to me. I try to set up the game difficulty and sliders so that if I play a "real" brand of football, and play mistake free and make my reads, I can be successful. I try to make it so that it's extremely difficult for the Bills to beat the Pats or Colts, while it's reasonable to expect a better game against the Jets, etc.
I can't stress enough how much small tweaks of the AI sliders make the game much more realistic and enjoyable.