Baseball has always tinkered with the mechanics of the game to equalize pitching and hitting so one doesn't over-dominate the other. I don't think they'll do anything as radical as move the mound back—I can't imagine the chaos of them suddenly having to completely overhaul their mechanics during the course of a winter and successfully compete at the highest level in mere months—but I do think they need to consider changes to the ball.
One idea I thought of many years ago that might help hitting is to make the ball heavier. My idea was to reduce ball movement on the way to the plate to make it cross the plate on a truer trajectory and hitters could square it up more often. And bonus, the ball won't get hit as far, which would reduce homers, keep more balls in the ballpark, and create more fielding and baserunning action which is more fun for fans.
Turns out there's a recent study that indicates that a heavier ball (i.e., six ounces vs five) might also reduce UCL injury in pitchers, because elbow varus torque would be reduced naturally, putting less pressure on the ligament and thus reducing exposure to rupture risk.
Whatever the answer is, I think it's better for the integrity of the game if it comes from changes in equipment over changes in dimensions.