OK, in the interest of giving us all somewhere to expand, how about we institute "unification" and "annexation" rules.
Unification
Unifying (bribing) a neutral city gives (.5*city size) points. For example, Warsaw (17 size city) would be worth 8.5 points while Krakow (8 size city) would be worth 4 points.
Bribery can get very expensive, so there is a positive reward for doing it.
Annexation
Let's use annexation as an excuse to get the major powers fighting proxy wars. The following are modified rules from "First Strike:"
For points, let's use the formula:
P=(.25*city size) IF contested by a great power (proxy war fought) and;
P=(.1*city size) if NOT contested by a great power.
So you can still get points either way, but there are many more to be made via peaceful annexation.
How to start a proxy war
Proxy Wars are started using Dario's Diplomacy tool (rember to save from both civ sides). You force war, and before you save your turn force peace, so that the AI won't attack you from another neutral country independent of the proxy war you're fighting.
If a player decides to start a proxy war, he must announce this 3 turns before he sends his units from his home ports. This gives the opposing side time enough to scramble troops for a counter move to the same country.
What you may bring
A player may only bring with him x100 (planes count x200 (including helicopters), ships nothing) worth of units in terms of shields of what the actual city size is. If a proxy war is started in a size 5 city, the player is allowed to bring with him 500 shields worth of units.
Whole countries are represented, so if the country has more than one city, the city sizes are added together as one city size to determine how many shields may be brought along.
If you lose units in the fight you may send in additional reserve forces. You can send unlimited units into the territory, as long as you stay within the shield limit.
How a proxy war is won and what you do afterwards
A player may claim victory in two cases
1. Annihilate the enemy force. 2. Capture and hold all cities for 5 turns.
After this a new proxy war can't be started for another 4 (1 game year) turns by the opposing side, so that remote participants in a future proxy war can prepare for the next assault.
EDIT: I edited the first page of rules. Please note I also included rules for "liberation" in addition to these (see first post for details).
The gist of it is if you want to reverse the annexation of major powers, you can liberate nations but must return them to neutral control (+5 for keeping your word, -5 for breaking it).
Further, I've barred the bribing of cities and units of human players. ONLY neutrals may be bribed (or any other civ that isn't played by a human, in case the Allies never get a player--which might be best, really).
Edit 2: Unless someone REALLY wants to play as the Allies, I have made them AI controlled. They will have the same "status" as the neutrals except I will probably feel compelled to defend all of them from annexation.