Germany and Italy get some lucky butterflies, coopt Vichy France as an equal Axis partner, and USSR as a treacherous temporary one, too.
The Soviet Union has no desire to see Germany in a position of hegemony. I repeat: Stalin may have been a paranoid psychopath, but he wasn't stupid. If Britain looks in a bad way, he'll turn the screw on Germany, not Britain. WHat does he have to gain? The southern hald of Iran? Wow, that's good value for an unchallenged hyper-militaristic neighbour who want to exterminate or enslave the people of Russia on his borders.
Their uber-Axis with Japan wipes out the British forces from North Africa, Middle East, and South East Asia,
How exactly do they go about "wiping out British forces in the Middle East"? Ninety percent of warfare is logistics, and the Germans, unless Rommel can wave his hands and shit railroad, don't have nearly enough logistical support. There are military buffs who can eplain better, but basically the whole North Africa show was a waste of time and resources for Germany because they couldn't reach any valuable targets without overstretching their logistical tail. There's this invading Turkey thing which is thrown around, but the Turks had recently shown how massive a headache it is to conquer the Anatolian plateau, and there army was respectable stuff. Whereas Germany overtaking the straits and heading for the back-door to the Caucasus is going to set alarm bells whooping and clanging in Moscow. Also, for Japan to attack Britain and the Netherlands but not America would enable the American forces in the Phillipines (which will be enlarged) to get the jump on them and leave thousands of Japanese troops stuck thumb-twiddling in Indonesia. America is completely capable of defeating Japan by itself. The Japanese knew this, which was of course why they tried to put American forces out of commision long enough to implement their plans. We know how well that worked out.
India rebels under INA leadership,
I'm not saying that if things looked grim in some hypothetical scenario, India wouldn't exit the war-effort stage-left, but I take issue with the INA being overhyped. The INA consisted of Subhas Chnadra Bose and some Malayso-Indian plantation workers assembled by the Japanese for propaganda purposes which they used on occasion as coolies. The
real "Indian national army" was the largest volunteer force ever raised, the British Indian Army. And again, I don't mean to romanticise British India or say that they'd Nevah Surrendah, but I just don't like all the credit Bose is given for being a pawn of the people who massacred Indians on the Andaman islands.
the British people eventually acknowledges their desperate situation
Okay, as I see it by some time in mid-1942, the most probably situation is that fighting in North Africa is ongoing, America is in the war against Japan at least, and if not Germany then FDR is moving it that way as fast as possible, the Japanese are at their high-tide in East Asia, and the Soviet ambassadors in London and Washington are having a lot of urgent chats. And of course the Germans are no closer whatsover to being able to subdue Great Britain by military means.
and the empty megalomania behind Churchill's braggadocio, and goes Germany 1918.
I'm of the "barmy anachronism who happened to be in the right place at the right time but honestly, Clem could have done better" school of Churchillology, but there's an important element to that that you're missing: the leader of the opposition could have been a succesful war leader. Since the military and diplomatic situation cannot be much grimmer than it was OTL (as I've said, either Japan attacks America or exposes itself to an attack by America, the Germans don't have much going for the in NA, and are the intact, formidable-looking Soviet armed forces poised to plunge into Poland so much less morale-heightening than the Soviet force who've just lost thousands of men at Kiev without that many shots being fired?), then who exactly is going to lead your coup?
Churchill dies trying to pull a Cromwell coup, George VI abdicates, Lloyd George and Edward VIII take over, Axis paratroopers land in southern Britain exploiting the revolutionary chaos,
IBC was last seen at the barricades in the burned husk of Edinburgh shouting "Come on, lads! Come on!"
Seriously, though, this is a revenge fic. If Churchill's perceived to have screwed up too badly, he'll be replaced with someone who can better prosecute the war by a parliamentary motion of no-confidance. Britain, as it turns out, is actually not 1918 Germany. Its 1942 Britain. Big differance there.
Britain surrenders, Canada, Australia, and NZ panic and seek protection by joining the USA, South Africa becomes an Axis client, India an opportunist nationalist neutral. Take that, Churchill.
Take that!
You're not really helping yourself with the whole revenge-fic-schtick.
Also, Australia
joins the USA? Its barely plausible with Canada.