Pretty much what you've already stated above.
We have one good OT and one young OT that might improve.
That's it. Nobody else on this roster can play Tackle in the NFL. And that is a problem.
We have one x receiver, one z receiver and then a handful of y's and backup quality receivers.
That's it. When Diggs or Davis goes down, this offense will quickly be playing with one hand tied behind it's back.
Mix that in with a new O-coordinator and a potentially more difficult schedule and I can see that unit having some issues at times.