Here's some stuff I emailed to my movie companion in the two after the film got out:
"Does it come with a happy ending?"
"We can't guarantee that."
Maybe the ending (of the film) is up to the imagination of the viewer.
Maybe Mr. Nick conceded the fight because Tony "chose" to be the fifth soul before going through the mirror, and Mr. Nick gives him that one even though it was on the wrong side of the mirror.
I still think there's a chance the whole bet was nullified and the Dr. got his immortality back.
And, either way, there might be a chance another deal was struck. Maybe Val got her "normal" life as part of a wager, maybe involving her daughter?
Imagery/cinematography/style choices I liked:
*Tony is lying on the ground after he first wakes up after being saved, and the doctor is crouching over him, face to face. Tony appears upside down to the audience.
*Valentina's red dress as she dances with the devil.
Symbolism, obvious and otherwise:
*The "His" and "Hers" mirrors. Val craves a pastoral domestic fantasy.
*"Rain on 5th." Complete with huge Chinese character for rain. It was pouring rain when Anton and Val dragged Tony up onto the bridge. The window of "Rain on 5th" frames the happy family like a painting.
Supremely Gilliam imagery:
*The Parnassus cop head with the unfurling tongue. Cops in lingerie for extra Pythonism.
*The Russian mother who removes her head to reveal Mr. Nick controlling her body with various levers.