Well, I'd say you have achieved what you wanted. Don't you agree?
You tried to live up to the challenge of photographing a white swan on white snow. Naturally the result would be "white and white and white". Now the swan has swan colours and the snow still looks very much like snow.
I find this a wonderful photo!
What more would you want to improve???
I mean: the swan's not even in a "typical swan position" - even its cleaning its feathers worked to your advantage!