Nice thread topic, Mojo.
I voted QB. It all starts there and I need to see Foles read his progressions better. Some deep accuracy, too. Progress on his footwork. Admittedly, it's a smal sampling, but still... The stakes at QB couldn't be higher regarding team success. Ironically, backup play of Keenum and Mannion has been surprisingly good, don't you think?
My second choice would have been coaching. Where's the fundamentals? Where's the efficiency? Where's the sustained drives resulting in a touchdown?
The OL is the soup du jour, I know. Too many rookies and a C position up in the air. But if we take out Washington's play, has there really been big glaring OL issues? Quite the opposite, IMO. They will gel and be fine. Not saying there won't be hiccups, mind you. But they will be much better than last year's OL.
Maybe games 3-4 can ease our fears. Hope so.