Why cant they add a 'catcher' to the barge?
The targeting computer for the rocket seems to be extremely accurate - why cant they add something like a, (fairly tall), flexible inverted cone wire cage on the deck that the rocket can settle into and clamp around the body of the thruster when it gets low enough, (and presumably prior to impact with the deck itself)? The accuracy of the targeting should be enough to get the booster reasonably central in the cage and the cone shape would take care of the final few feet of lateral displacement..
It seems to me that would negate the need for actual hard landing capability and provide the booster with stabilisation after the rocket engines are shut down... might also allow for landing in rougher seas too if the cage were to grab the booster high enough up the tube..