No Nukes means Operation Downfall. While the war goes on the US pulls more troops out of Europe [fewer war brides].Fewer troops -less denazification.
Russia will also continue to pull front line troops out of East Europe, which means minor Butterflies in Russian take over there,
OTL The Korean N/S border was reached in Negotiations, Here where the Japanese are still fighting I wonder if the Negotiation would be the same.
The war continuing into 1946 means a lot more Lead Lease being sent to China.
It wasn't till late summer 1945 that the US agreed on a Commonwealth Force being included. and when the bombs were dropped, it was in California training.
I don't think the US would accept a Russian invasion of the Islands.
By Decembre when the invasion starts, whe will have had 90 extra days of Bombing, While it will be bloody, I doubt the Official estimates, Specially as they are in such disagreement with each other.
With the much greater damage, I expect to see even more Westernization. I would not be surprised if Japan adopts Roman Letters
However the Asian Dragons will be slower taking off.
With the US focused more in Asia, I see a sooner stronger SEATO.