I think London defense was boosted too much in Alpha 3.9 (Sea lion should remain viable in the right circumstances). We generally remove one inf, and one AA gun from UK to make them build ground units there. I will say that I like the new Royal Navy arrangement around England. It should still be a challenge for the Germans to pull off Sea lion, and keep on pace if/when they do.
As for the Russian bomber, we tried that once (seemed like they should have one). How it turned out was it ended up on England paired with the Russian sub to take out German blocker ships (sz 110) for the Western allies to attack Norway. This hardly seemed historical, so we haven’t given Russia a bomber since.
The Italian NO? Yeah we have house ruled it a couple ways too. Always only mainland Europe & Mid East (no African safari, or island hopping w/US or UK transports). We have allowed for the pro allied and strict neutrals if axis take them (or activate them) as mentioned in other posts. Normally 2 IPC for neutrals (depending on which ones are allowed), 3 IPCs for orig Ger/Ita.
We have also looked at splitting the Russian lend lease NO. Awarding 3 IPCs for the way it is in the rules, and 3 IPCs for a Mid east route. Allied control of of sz 80m, NW Persia, Persia, and Caucasus (sometimes also include Stalingrad). One game Italy got whacked early, so w/o much axis involvement in the Mid East it just seemed like a give-me for the southern route, and Russia also getting paid for those neutrals was a cash cow for them (balance). Just saying watch what you put in the game. By all means experiment, but balance is thrown off quite easily…