There's a lot to be concerned about, but there are a few that really stand out to me:
1. Offensive line has regressed as year has went along, and everything starts up front. If the line can't open holes, no running game. No running game, no play-action, which was our strength earlier in the year. Age, maybe?
2. Goff is off. Partly the O-line, partly trying to do too much. Hopefully not signs of happy feet or early onset Bulgeritis. He's made some crap reads, stared down receivers, and sailed a lot of passes, three straight weeks. Too early to tell if he's the next Brady or the next Andy Dalton.
3. Defense in general. Lots of big names but no cohesion, no consistent stretches of great play. Has any "dream team" of free agents ever really turned into a dominant unit? We lose gaps and edge consistently against the run, and our secondary has at least 2-3 blown coverages a game. Linebackers can't cover the tight end, and we lack a shutdown corner. All we needed was for the defense to be above average to good, but they've been mediocre to poor, which was a big disappointment. Offense covered them for the first half of the season, but definitely exposed of late.
4.Some worrisome decisions in coaching on both sides of the ball. Too much reliance on 11 personnel, abandoning the running game, continuing to try to throw deep when protection isn't there on O. On D, trying to make Peters an on the ball cb, unwillingness to blitz more, staying with Barron and other lbs when it's clear it's not working. Maybe the bench isn't any better, but when what you have isn't working...
Right now we look like the early 80s Chargers: tons of passing yards and points during the regular season, but turnovers and bad D caught up to them in the playoffs. In 1980, they were 4th in offense, 18th in D. We're 2nd and 20th. Unless we get things on track in two short weeks, I think it's one and done again, with some serious questions about D, including scheme, and O line and whether other teams have figured out our O.