Hmmm, an interesting set of ideas. I am planning to do the same, using the original Pacific and European games for my summer history class and historical gaming class. I have some home rules for Pacific that I use, where I have increased the game to 6 players: the US, British India, Australia, the Netherlands East Indies, China, and Japan. For the European Game, I am planning to add Italy, using the pieces from the Anniversary edition. There will be theater commanders for the US and the UK in Europe and the Pacific, and a separate commander for Australia.
I do have rules for Lend-Lease, and also Lend-Lease certificates that I use. I have modified the rules a bit for aircraft and shore bombardment, and Japanese Infantry are a bit harder to kill. When I add Italy, it will have the option of changing sides during the game, or even staying neutral. It does mean reworking the IPC for the Europe game, but such is life. Should be interesting when it is finished. I am also writing a combined rules set for the game.