I know. WTF?
One theought, the ending was from Tony’s point of view as he is whacked. Everything just ends instantly, right when you least expect it.
Another thought, I heard they filmed 5 different endings. Looked like they didn’t use any of them. So they put out a special collectors DVD with all 5 endings. Sales will be huge.
(Damn!) already deleted it, but in retrospect I think you got it.
Flashback shirt, antique diner and music, everybody happy (Willow no longer the self control freak & AJ acting almost human)....
Tony gets his notice and goes out remembering the good times.