The ironic thing about Marion is that he's taking many fewer three-point shots, and I think we'd all agree that's a good thing. But somehow that has taken him completely out of his offense. He's never been good at creating his own shot, and now that he is a reduced threat from beyond the arc (for the simple reason that he hangs out there less than he used to), he just doesn't have much room to operate.
I also think the Suns' defense is worse than last year's. They used a gimmicky trapping swarming defense against the Spurs in the playoffs, and it was pretty effective -- but they had to try something, because otherwise they would simply have been eaten alive by the league MVP. Do they have to play a gimmicky defense against every team in the league? I wouldn't think so, but that's what they do: constant double teaming, "bigs" jumping out high in exactly the way that Errntknght hates, playing the man with the ball far to one side in order to give him a driving lane into where the help is supposed to be, etc. It's as though the Suns simply don't believe they can be an adequate defensive team straight-up.
Somehow, Marion and Stoudemire have to step up. Otherwise, it's going to be a very long year.