Well the physical problem with a stalemate in 43 is that if Germany moves a large number of its forces to fight in the West, that's just asking for the Russians to reorganize their forces and attack again once the Wehrmacht and WAllies are killing each in large numbers in France.
IMO if Germany played their cards right they could inflict massive strategic defeats upon the Russians in 1941 but not get trapped somewhere trying to swallow the country whole, fight an increasingly more effective defensive war against the advancing Soviet armies (to be fought principally in Ukraine and Byelorussia) and, having not lost a ton of men and machines in doomed operations like Stalingrad and Moscow, fortify and hold an area approximating from Odessa or so north to the Baltic Sea, including Western Ukraine and eastern Poland.
With some luck, the Russians won't be as efficient in using troops, and hence take massive losses just to get the 1939 borders back.
Once this goal is achieved in late 1942 or so, Stalin will think "hey the German army is still quite powerful and now back on their own turf, look how many guys it took me just to get my own land back", and call it quits. In exchange for ending the war (or calling a cease-fire), the Soviets get their 1939 borders back, minus whatever their took from Finland, which as a result of this leaves the Axis to become neutral. The Germans get free reign over everything west of the USSR.
With the Nazis and Soviets making peace, the WAllies now have a massive problem if they want to continue the war. Sure from our perspective they'll have nukes in two or three years, but nobody except a few people know that in 1942, and even then they might not be sure the bombs will work. On the other hand, the USSR and its massive armies are no longer in the fight,leaving that many more experienced and specialized-in-the-art-of-defensive-fighting Wehrmacht divisions to beat the crap out of any attempt to land on the Continent. Many will want to keep fighting so they can get their homelands back, but in the end the WAllies are going to call it quits as well. Germany now has eastern Europe minus the USSR, is allied to Italy, controls France, Denmark and Benelux, as well as Norway, which on second thoughts actually might get its independence back during negotiations since the RN can probably take it easily anyhow.
After this war, Germany will have retained a good chunk of its empire, but it will be the absolute pariah state, like North Korea except that people actually fear it. The West will be pissed at the Soviets for giving up like they did in WW1, and likewise the Soviets will proudly proclaim that they literally did all the fighting they could while the West just stood by and watched. Meanwhile, Germany will probably have gone through some kind of power struggle or reset, and besides that become more oppressive of their populations, both Germanic and not. They will also pour more and more money into superweapons in the hope that they can achieve MAD with the US and USSR.
I say long-range missiles by 1946, and nukes by 1950.