The play-calling and execution on offense simply aren't good enough
The Cardinals have an excellent defense, but six points on 262 total yards simply isn't good enough. Along the same lines, a stat line of 183 yards, no touchdowns and an interception from Matthew Stafford also isn't good enough. He has to play better going forward, as does the offensive line and other players who are responsible for blocking (I'm looking at you, Eric Ebron). Heck, just generally speaking, the Lions' offensive players have to elevate their game.
At the same time, offensive coordinator Joe Lombardi has to elevate his play-calling. The Lions' offensive game plan on Sunday was downright putrid, and this sadly is nothing new. Injuries and adjusting to a new system were valid excuses earlier in the season, but Lombardi simply has to start putting the offense in a better position to succeed. His current play-calling is not getting the job done, and it's really holding this team back considering how good the defense has been all season.
The sky isn't falling
I know fans are a bit overdue for a meltdown considering this was the Lions' first defeat since early October, but there's no reason to panic after a one-score loss on the road against the best team in football. There is definitely reason to be concerned about the offense, but the good news is that the Lions have a defense that should keep them in games week in and week out.
What's more, despite the loss and the Green Bay Packers' win on Sunday, the Lions are still technically in first place in the NFC North, and they still control the No. 2 seed in the NFC. The Lions definitely have less room for error going forward with the Packers having the same record as them, and next week will be tough with the Lions going on the road against the New England Patriots. But the Lions are still in a pretty good spot all things considered.
NFL officiating needs a complete overhaul
As you are well aware by now, NFL officiating is not good. It's never been good, and it will never be good as long as the current system remains in place. You can really pick out at least three or four questionable calls from every single game that is played, and Sunday's Lions game was good evidence of that with Jerome Boger's crew making a mockery of the rulebook.
But that leads me to the bigger problem that exists: the NFL rulebook is too complicated and features far too much gray area. If the NFL really wants to start improving officiating, it needs to simplify the rulebook and clarify things like what constitutes a downed punt. We shouldn't still have so much uncertainty about something like that in the year 2014.
Making the rulebook simpler is only part of the solution, though. The reality is that the NFL needs to spend more time training its officials, and there needs to be more accountability for them given their impact on games. Mistakes are bound to happen, and things like judgment calls will always depend on your point of view, but there's no excuse for administering the game improperly or flat out blowing obvious calls.
I get that officials have a tough job, and sometimes they simply can't win given the rulebook they have to work with. But officiating seems to be as bad as ever, and it's really degrading the experience of watching NFL games. The process of improving the officiating is far from simple, but something has to be done going forward, because the current system is broken.