If you have players that want to have a Yalta conference before every Russia turn or US/China/UK turns, then that’s one consideration. Put another way, if the US player is going to want to know exactly what China, UK and Anzac will do before it does anything, this could slow gameplay down.
IMO, the game slows down the most between Japan and US, since Japan has so many options and US can’t know what to do and how to split its builds until it sees what Japan does. But while US contemplates, all the rest of the players can be considering their next moves.
So basically I agree with YG except that I think China can be split off from UK Pac just so UK pac can be thinking about its builds after Japan moves, rather than having to plan China. Russia and China can benefit from a bit of coordination, and if the axis are slow to invade, the Russian player is in the thick of the game quicker.
Player 1: Germany
Player 2: Japan
Player 3: Italy
Player 4: Soviet Union / China
Player 5: United States
Player 6: UK Europe / France
Player 7: UK Pacific / ANZAC
Just a question though, since I have never actually played this: when UK is split, could there be a conflict if UK med boats move to the Indian Ocean? Who would control them? Or sending fighters from Africa to India, or vice versa? The split sounds good in theory but does it work in practice?