I'll say this much. In the 2.0 engine, the concept of choosing a defense that was % run vs pass was probably the right thing to do. There were no other options to control your defense. In this engine, the concept of choosing run vs pass % is totally ridiculous. Let me set my formation, my players, where they line up, who blitzes and how often, and how deep to set my coverage. THEN LET GAME INSTINCT RULE THE GAME. If I put 8 in the box and the opponent goes deep and gets a big play...then good for him. My mistake. My guys should either react or get beaten.
Secondly, random may not be the technically correct word. Perhaps its more "inconsistent and/or unpredictable". It appears that there are so many "inputs/factors" being used on a given play, that it is impossible to figure out which one or group of factors actually influences a given play.
Lastly, in 2.0 every formation (offense and defense) was effective if you recruited for it. In 3.0, there are formations that are completely ineffective no matter what you do. (Not saying 2.0 was better, just pointing out a difference for the sake of argument).