So if the PODs allow Germany to beat the Soviets you have a scenerio where likely the Allies can clear Africa and some of the Mediterranenan Islands but can't invade Europe due to German ground strength (and incremental increases in air power).
A Japan first scenerio is likely then, and once that is over superfortresses rain conventional bombs, once the mustang comes online the Germans can't stop that. The allies figure out how to destroy oil centers, refineries and such places that hurt the German air effort.
But likely this isn't enough as there are still lots places to disperse industry, lots of slave labor available. The Allies will get the ABomb but worry the Germans will relatiate with Sarin loaded in V-Weapons which are just across the channel.
A cruel world indeed. Hopefully Hiler just dies late 45 and the German regime collapses of its own incompetence.
You seem to have a bit of overoptimism about the P-51, which essentailly was only so good, due to the lack of German experienced pilots, as these already had died, mostly in Russia. With no setback in the USSR, the german industry would have had the time to build up forces, more clapable, with the then still in existence pilots of veteran level. No P-51 can change that, I am afraid to say.
First of all, german technology was more advanged than the US one in most modern weapon developments. (Rockets, cruisemisslies, guided weapons, jets, submarines, etc.) You cannot ignore that. B-29's are easy pickings as they were large and not the most manouvreble types of aircraft. A fast jet, especially fitted with AAM's of the early German generation, becomming online around 1945, would empty the skies over Germany of daylight bombers. Ground to Air missles were also already reaching operational status in late 1944, so could have made bombingmissions a nightmare. (No slowing down of this development expected, with the USSR out of the way.) German Air Defenses were the most advanced of their day, with airsearch radar networks, warning the airdefence fighterbases as soon as the bombers left the UK soil. The fact that it did not work well in the OTL was the almost complete absense of the Luftwaffe in West Europe in the later waryears, due to their operations in the East. Tehre simply were too few aircraft left to intecept the bombers.
Nuclear weapons too have no change to change the landwar, as you simply have not enough of them to destroy an army on an entire continent. It will only result in unwanted retaliation, which the UK was not wanting and the USA unwilling to be reponsible for. (It might have caused the UK to force the USA not to use the nuclear weapon in the first place, as the price would be paid by the UK alone. The USA were not so stupid, to risk loosing their only real ally.)
A sort of stalemate wa more likely, as the Germans could not realy threaten the UK and USA, while the same thing was true the opposit way. A new world order would emerge most likely, with the USA and USSR pair now changed into a USA vs Germany as remainigng superpowers.)