They actually have a pretty good young nucleus thanks to finally putting together a few good drafts, which has been key. Injuries absolutely hurt them this year, and I think the Marcus Jones one was tough because he could have at least given them some added speed on offense, which they're obviously missing. Not to mention their depth on defense.
I think the biggest mistake was also banking on Parker to be more than he is. He's a guy who looks like he's working his butt off one game, only to look like he's going through the motions during the next. Curious to see how he performs with Zappe ... again, I don't think he and Mac were ever on the same page.
I think their biggest mistake was in not getting a veteran QB last offseason. Bringing in Gardner Minshew could have given them some semblance of a pro offense.