Not sure that this changes a whole lot; by March of 46' the Japanese surrendered because the Soviets have torn them apart wholesale. If the USN had performed better, there might not be an Japanese Democratic Republic on Hokkaido and Northern Honshu.
In OTL, the question is whether they wanted their Emperor to enjoy Stalin's tender mercy or the Allies; with the Red Army close to enlarging their toehold on Honshu, the IJA folded to the Allies.
If Midway is won, would the USA have the political will for CAPSTONE? Some planners proposed simply burning Japanese Cities to the ground with incendiaries and the nuclear bombs. The point is; the Soviets are the ones that forced Japan to terms OTL--and they had nine months to wail on them.
So we assume that the Battle of Midway turns into the Battle of Darwin: The IJN is gutted and left only capable of a halting defense. Obviously, there will be no odd encounters of Japanese Soldiers being found years later in the Great Sandy Desert, some of them well into the 50s.
But that has little military impact. I presume that Bull Halsey probably survives the battle, and the USA probably does close in on the Home Islands themselves. But what then?
The Soviets encountered Kamikaze and Kaiten suicide weapons in their conquest of Hokkaido, and fierce resistance on Honshu to a degree that the Soviets couldn't even get off the beaches.
The idea of trying to take Kyushu or the Kanto Plain is pure folly. Japan would undoubtedly dedicate its last measures of strength to ensure that any attempt inland would be purchased at an unbearable price.
It just seems impossible that the USA would easily beat Japan without massive Soviet Help, which is the real game changer here. If it were somehow possible, the USA could well clear Korea and Manchuria and keep the Nationalists in power in China. No Communist Korea, North Japan, or Vietnam either.
In the end, I guess it worked out rather well. Communist China and the Soviet Union soon discovered that Communism does little to address historic grievances, and I think that short of the Nationalists winning the CCW, the Sino-Soviet issues will boil over.
That Ussuri River stuff--good lord, that could have killed us all. I think we can all thank our lucky stars that NATO was able to broker a truce before those missiles went off.