ps. Another thing you might consider, given that you are already open to adjusting the value on the map, would be to move some IPCs from the core to the periphery, or adjust the core and use a base of 10 ipcs for all capitals.
In the old games when I would try to add Italy (to Classic or Revised) we always started Italy with 8, since that was the lowest value of any capital territory on the old boards. AA50 has some capitals at 6 rather than 8, and used a more low production scheme (but built on the idea of indirect National Objective money). On 1942.2 the lowest value capital is again at 8 ipc, so I would at least have Italy itself (Rome) at 8 ipcs. 8 minimum just to be a functional player without NOs.
On the other hand, if you went universally with a 10 ipc base value for all capitals on the map, then you could move 2 ipcs from Eastern USA somewhere else more contested, so that Washington DC matched the rest of the six powers all at a value of 10.
UK, Russia, and Japan would benefit. Germany wouldn’t benefit, since they already have a capital at 10. USA would be knocked down a peg to 10 on E. US, but this likely wouldn’t alter the Atlantic dynamic too substantially. This might be used to round out the starting numbers if desired. The advantage here would be that you could start Italy at 10, on the rationale that all major players start with a capital worth exactly 10 ipcs.
It abstractly puts all powers on an equal footing (at least as far as their capitals go.) Germany and Japan easily overtake Moscow in 1942.2 OOB. And UK is too cash strapped to do much in the Atlantic and India at the same time. So it folds at the center. Moscow at 10 would probably make the situation easier to manage at the center. J at 10 would make KJF harder. London at 10 would make cross channel invasions more challenging for G, easier for UK. So the trick would be to have the other production values on the map offset what you do in the core. Forcing a Pacific game would do a lot to hold off the center crunch. For units and base values, I guess 1942.2 is the model, but with AA50 aspects? Or does ILs map include other adjustments? I think it’s OOB right, for the territory and sz divisions?
I am always wishing for an A&A game with cleaner start numbers for income. In increments of 5 or 10, you know, numbers that fit the crisps 5 or 10 dollar bills ;)
Without knowing anything else about the planned set up I like the following numbers as guides, just for their quick and clean doling out at the beginning. Relative strength at…
Italy 15/20
Germany 45/50
Russia 35/40
UK 40
Japan 40
USA 50/55
These numbers (assuming no other bonuses are in play), would still provide a lot of options for opening buys. Much depends on how Italy is integrated. Would they go first, or last, or somewhere in between? And then of course the question of how to keep Germany functional and interesting once Italy is integrated.