I really don't have a problem with what happens in the movie as far as the claws go.
In the comics I never liked that they removed the adamantium from his bones but I did think him having bones claws the whole time and not knowing it was awesome.
I didn't even think about it while watching the movie so I don't think it was needed.
By the way when is Kayla mentioned in the movie? I had seen it mentioned that she's referenced and was waiting for it but still missed it.