The Expendables 4

I dunno, John Wick which in my opinion is the best action film of the last decade had the most basic back story I can't help but to think if they went into a lot of detail about him upfront it might not of been as good.

Now with the second chapter they added to the character (which was fine) but not enough to distract from the action and above all it didn't distract from the basics.

Mad Max Fury Road was similar, big set pieces with little back story for the new characters, I think it works better that way for action films.