My suggestions were playtested several times with OOB Rules:
Set Up:
5 additional Infantry and 3 Additional Artillery in Hannover.
1 German Cruiser in SZ 26.
Map:
Switzerland is worth 3-4 IPCs
Russian Revolution:
RR occurs if Russian Homeland-tts (Look for definiton in the PTR) worth 10 IPC are occupied by the CPs after the Russian Players Turn.
Russia is required to immediately surrender and leave the game at that time. It no longer has a turn, and all of its land, air, and sea units are removed from the board. Control of any territories that it was contesting is established, if necessary, using the rules for moving all units on one side out of a contested territory (see “Land Units”, page 15 of the rulebook). It also loses control of any territories that it controls, including its homeland territories. If units belonging to other powers on the same side are in these territories, control will likewise be established using the rules for moving all units on one side out of a contested territory; otherwise these territories will be uncontrolled (place any national control marker on it face down to denote this status) until another power moves into them. If a territory originally controlled by the surrendered power is captured by one if its former allies, the capturing power takes control of it. Russias IPC treasury will be claimed by the first enemy power to gain control of its capital.
Unrestricted Submarine Warfare:
USW takes place in SZs � 2,3,4,7,8,9,15.
German player roles one dice for EVERY Sub that is in one of that SZs when it comes to collect income for the British player.
The result will be split up between BE and US. (If its an odd number, the Brits suffer more)
If US loses income for a second time, it will enter the war. (Generally US declares war R4, so beginning USW in R3 won´t change that)