If you like The Man Who Knew Too Little, then perhaps you will also like Mr. Right. Both use obliviousness as a form of comedy. There are also presumably some similarities with the TV show Dexter, which I haven’t seen, but which revolves around a serial killer who kills killers.
There was some cleverness and fun action, but I didn’t genuinely like the characters and felt squeamish about some of the violence.
Perhaps the best part of the movie was Francis’s interaction with Steve, an assassin sent to kill him.
Also enjoyable was hearing Tim Roth, who I recognize from the TV show Lie to Me, put on a southern drawl that is not at all like his usual voice.