They don't have to threaten them just occupy them, and IMO Peterson and Sherman are the only two to be overly concerned about. The other can be beat.
The idea that any single player needs to dominate the "corners in our division" is short sighted. The best way to attack the defenses in our division is to RUN THE BALL, and be successful at it. Look at the MNF game vs. Seattle. I don't remember Sherman being any kind of factor in that game. Why? Because the Rams pounded the ball on Seattle to the tune of 200+ yards. Were it now for two horrible throws from Clemens, that game never would have come down to the final series.
Same can be said about the 49ers, although not to the same degree. Their secondary can be exploited, but they do need to establish they can run the ball in order to use the play action passing game that was so effective in the 2012 season vs. SF.
Arizona's secondary is not as good as Seattle's, but better than San Francisco's. But as was the case in the opener last year, can be exploited by attacking the seams. Again, run the ball, force them into over committing to stopping the run, force them into man coverage and get Austin and Cook involved.
The pieces are in place. But as is often the case, for this team to be productive on offense, it HAS to start with a solid running game.
A point I think is worth mentioning.... this article (as are way too many) focuses on Bradford and his future to the stability of having Schottenheimer back for a 3rd season. As a few have mentioned, I think it actually benefits the ENTIRE OFFENSE, especially the younger skill position players even more than it will benefit Bradford. And therefore, it becomes a domino effect. The better they understand the nuances of the offense, the more Bradford benefits.