You are in uncharted territory here my friend!
You’ve got to understand that since the game was not intended to be played the way you are doing, you will probably need several rules tweaks in order to balance it out. I’m NOT telling you you shouldn’t play this way–I’m sure its fun! Just you might be facing a situation where the rules need to be adjusted to reflect the new 5-way balance…
Try making friends w/ USSR, that will help. What do you guys bargain w/: IPCs, territories–what? An alliance w/ Japan might help a LOT too–have them help you out in Africa. Otherwise, build a strong fleet the first few turns when you’ve got the cash. That way when you are poor, hopefully all you’ll hafta build is INF and funnel them to Africa until you win.
Have you ever played Diplomacy? Totally different combat rules, but it very much has the flavor you might be looking for in 5-way A&A: lots of secret deals, shifting alliances, every man (or woman, though I find women tend to hate this game) for him (her?) self etc. Plus, Diplomacy has been playtested for decades to be played in just this manner, unlike A & A, where it is a variant rule. Just an idea…
Ozone27