I have played many 5-way “every man for himself” A&A games. We’ve done it two ways, both original setup for each player (using the reference cards) and the scanario where everyone gets an equal number of units at the beginning, all to be placed on their capitals. We like the latter better, but both work.
For both versions, we set a time limit, and whoever has gained the most territory points at the end of the last round wins. Each player gets his country assignment randomly, and yes, it definitely makes a difference. GB is the toughest by far, so that player will have to use diplomacy to survive. Germany and Russia will fight each other to the death unless they form a nonagression pact (which is usually broken eventually). Japan and th US are in the best positions to win, but often end up in a similiar war of attrition as Germany/Russia.
I love this version of the game because it is totally open-ended, there’s no tried and true strategy to win. We make everything tradeable, IPC’s, territories, units, whatever. If you can make a deal, go for it. The only rule is that trades must be physically transacted during one of the “traders” turns.
Other than that, all standard rules apply. This might be right up your alley, Patriot. Give it a shot.