Of all the teams the Cards are most dependent upon the QB's health. The Niners have Rosen a better-than-average backup. The Hawks have Geno Smith, not a quality starter but not completely a train wreck either due to their run game, OL, and offensive scheme. AZ has Colt McCoy who has started only 5 games, played the last 3 years throwing 4 TDs to 5 INTs and an average of 108 yds per game. He's not a running QB so their offense will go nowhere with him. Smith isn't much better but at least he wasn't turning the ball over in his games the last 3 years with about the same number of appearances.
One halfway serious ding to Murray and the Card's season is over in this division. That is the problem when you have a running QB who comes in with minimal experience in reading pass defenses. Both Mahomes and Lamar Jackson are running QBs who have developed their pocket presence. Mayfield was like Murray a one-read then-run QB until he began to show development as being able to get beyond that. Murray showed a bit more last year but not near enough.
It's why I see the Niners as fighting it out with the Hawks for the #2 & #3 position. The Rams and Niners have the best backup QBs in the NFCW. The Niners also have a better defense compared to the Hawks and Cards.
Rams, Niners, Hawks, Cards
I think the Cards will be lucky to finish 9-8 with the reverse more likely.