The fact that there is little mystery to the film shouldn't matter if character and feeling are what you are seeking. The reveal at the end is less of a surprise than the action of the climax. And in typical Sheridan fashion the climax is never the conclusion of the story. Time must be taken to recover. That is time where most people live in a world without mercy.
Even if you are not a fan of the recent spate of pale remakes that come along with every generation, this update is worth your time. It will take a spot in my collection, to be sure. Right after Kurosawa.