I agree with much of what ljay889 says. I saw the show last night for the second time, and was really impressed at how all of the performances - particularly Geneva Carr's - seemed even better than when I saw them in April. They really seem to be enjoying what they do up there on that stage. I think I enjoyed the play itself more the 2nd time too.
On to Bob Saget: in the first act, I was thinking "oy, he's actually not very good," but he turned me around in the second act. Even his projection (which ljay accurately pointed out is not very strong), improved in the act 2. Pastor Greg really starts to break down in the second act, and I think he pulled that off very well. I agree that he was more shy and genuine than Kudisch. Overall, I would say Kudisch was better, but it was still a treat to see Saget onstage.
For the stage-door: he came out around 10:30 I think. He was very kind and generous with his time. He signed, posed for pictures and chatted with his fans. The crowd wasn't too bad at all. They still use the same v-shaped barrier formation they had before Saget joined the cast, and there seemed to be enough room for everyone.