RG Ron Stone is a solid player who is capable of being a very good player. Former starter LG Greg Bishop was allowed to leave via free agency. He's not a bad player and he is actually capable of improving, but the Giants would be well advised to add at least one more quality body here.
Depth is also a concern.
He finished strong and there are hopes that new Offensive Line Coach Jim McNally will have a big positive influence on him. Toby Myles is also waiting in the wings. He's a heck of an athlete, but he still has to prove if he can be a heck of a football player. Much depends on whether Gragg and Myles develop and if the Giants move Gragg to guard. If they really want Gragg at guard, then right tackle becomes the number one need, not left guard.