Yeah, there were some great laugh out loud moments in the finale; I think you're right that Jesse's "hey Mabel!" was the best.
I'd be happy if that's the last we see of all of the Annville residents, though. (Arseface excepted, of course.)
The God scene was... strange. Not sure how I feel about it. Obviously, it was meant to look like crap. But I feel like they went too far in that direction. Maybe if their interaction with the fake God was a lot shorter it wouldn't have bothered me.
The last few minutes were great. I had a huge grin on my face finally seeing Jesse, Tulip, and Cassidy take to the road.
Oh, and I hope last episode is not the last we see of DeBlanc. Could be, though, as the Saint's bullets are meant to be fatal for everyone, even angels/demons.