Ooo I just watched this last night. Whilst I too thought it was going to be a lot more fun before I watched it (not because of any trailer, I almost never see trailers before watching films) I still really loved it.

I think I was expecting something more like Hot Fuzz for some reason? But it fell more in line with Martin McDonagh's other films and that still works well for me. It has it's own type of comedy that I enjoy (love a good jest against the Americans).

Can't say much about the trailer, maybe next time don't watch trailers? I find going in with a loose sense of what the movie is about is best and surprise surprise you get less misled cause there wasn't much there to mislead you from the start.