Italy taking London?! Now I’m intrigued! That sounds crazy awesome. Have no idea how it could work. A risky move, no doubt. Like letting Italy clean up Paris after Germany does the dirty work. I’m a big fan of non traditional strategies.
You your self (Flash) have said many times that the US had control of the Pacific Theater and should be allowed joint ventures. W/Anzac it opens up the door to combined attacks, w/o involving two major (overpowering) countries. I still think its a step in the right direction, with some tweaks you could get more of what you want.