If the German Bombers get through on G1 and G2 he does not lose as much in the invasion as one might think. 2 bombers average 11 points of damage now. So that leaves me 28 less 11, only 17 points to buy troops on UK1. So 5 Inf. But UK does not have to buy off all the bomb damage, 1 IPC to get to 10 damage, and then pay just 4 IPC’s per infantry (3 for the infantry and 1 IPC to repair the factory for the unit. So 6 infantry. 7 infantry if UK gets a little lucky on bomb damage.
If I get the Italians in Africa, the UK will collect 28+1 (africa territory) +2 for Persia and +5 for NO bonus. Assuming no submarine convoy disruption, that is 36 IPC’s. But will lose 11 IPC’s (if UK shoots down 1 bomber on G2) or 16 IPC’s if all three get through. 16-6 to get to 10 damage, and 4 IPC per infantry, so 7 more infantry.
Absent some luck on anti-aircraft, UK will defend with 17 Infantry, 1 Artillery, 1 Bomber, 6 Fighters and 1 Tactical Bomber vs Germany’s 16-26 ground troops, 5 Fighters, Tactical Bombers and 3 Bombers.+ Assuming 11 Transports, that is 22 ground troops plus planes so - Germany loses about 2 planes to anti-aircraft and 16 ground troops in the invasion. They capture London 99% of the time. They still have AC, wounded BB, 1 CA and 4 Fighters, 4 Tactical Bombers and 3 Bombers surviving to protect England from America. This assumes no naval attack on UK1 or UK 2.
So I might as well attack their fleet on UK 1 in the hopes of exchanging ships for planes and I can retreat back to England if things go bad to save the planes. Not a great attack, but I am not going to use the ships if London falls anyway.