Better in what way?
The Yamato was designed for a very questionable strategic goal, one that was disappearing even as she was commissioned. Unlike her USN counterparts, Yamato was poorly armed to act as a close AAA escort, arguably she was hard pressed to defend herself less due to the lack of medium size AAA and more to the train rate of the gun mounts. The ship was also prone to very severe concussive/blast effects when firing her main battery, IJN personnel indicated that blast effects on the bridge were especially serious.
If the goal is a better battleship than her design should have been balanced (i.e. her armor should have been sufficient to stop her own gunfire). This is a difficult task (the U.S. Iowa class is not a balanced design despite being arguably the best protected warship class ever to sail) but it was always the designer's goal when putting the ship. That would have required an even larger design, as would a design that would have allowed her to maintain formation with the "fast BB" of the Kongo class.
Most of the other improvements have to do with train rate, elevation rates, and electronics (especially gun-laying radars). The Yamato design was the perfect 1930 battleship. Unfortunately she wasn't commissioned until December of 1941.