The fight in the movie didn't really give us an answer of whose more powerful between Thor and Hulk. It purposely left that ambiguous.
You had Hulk seemingly winning towards the end but fighting a Thor who was only trying to restrain the Hulk and clearly not able to go all out with his Lightning and other more exotic powers in that scenario.
However going by feats from the Avengers, IH and Thor movies, Thor definitely seems to have the more powerful feats.
Which is similar to how the comics portray them. Generally in the comics Hulk has been shown to be stronger whilst Thor more overall powerful. But a lot of the time Thor will end up slugging it out with Hulk giving Hulk the edge (just like in the movie).