Its not so much uneven cratering; 'our' side of the Moon has suffered the massive Maria forming events where as the farside did not.
This is a real mystery.
Although the Moon was closer to the Earth in the past it could not have been so close for the Earth to physically protect it as a shield, because that would require the Moon being well within the Earth's Roche limit and it would have broken up.
There is a second mystery here - the same is also true for the Earth; we call the Earth's Mare the Pacific Ocean! In the past it was even bigger as the land masses were all one continent - Pangea.