I think it's just that the lights actually play an almost side role in this shot, they are just hidden away in the top left just about to go out of the shot and to be honest they don't actually look like Christmas lights. They just look like the kind of outdoor lights some people use at any time of the year.
I think it's back to the drawing board with this one but go out and try again, not further adjusting of this one.
You've got 25 days left before Christmas so I am sure you'll be an expert by then
Cheers,
Rob