If I recall my history correctly, the Germans didn't try very hard to kick the Greeks out of the war. They shrewdly noted that the best way to keep Bulgaria engaged was to give them a front to manage, close to home. Had they occuipied Greece, it was likely that Bulgaria would drag its feet about in the other theatres - not an issue at all in this game. Much better to tie up Entente resources in Salonika with troops they can't use elsewhere. If they put their mind to it, I don't see how the Greeks could possibly hold against a determined assault.
Perhaps one way to balance this would be to make Greece less of a prize for either side. Currently Greece has 35-40 MPPs worth of resources, although the Brits really only see 28 MPPs from the convoy. It is safe to assume that the CP would see a similar amount to the British. That's a 60 MPP swing once occupied. Additionally, the Brits can use the Greeks to build an artillery unit. This makes Greece impossible to ignore. It might be a good idea to remove that artillery unit and reduce the amount of resources that Greece has. Further increasing the cost of occupation with partisan tiles in awkward positions in the mountains throughout the country would make it even less enticing. It really seems strange that the Greek economy, a largely agrarian one, is over double that of the Netherlands, a heavily industrialised country in possession of some of the most resource rich colonies in the world.
In terms of assessing game balance I think it is also very useful to break the game down into the various main fronts that regularly occur. To my way of thinking the Western Front is very unbalanced because the Entente (realistically UK and France) has more artillery pieces than Germany right throughout the war. This is not historically correct. When the USA turns up the situation becomes ludicrous as they can add 4 more artillery pieces in the later game (if the Central Powers can get that far).
It is not as big a problem as you think. The French get 3, the Brits 4. At least 1 has to go to Egypt, 1 to Mesopotamia, 1 to the Balkans if it is still standing, and 1 to Italy. This leads to 3-4 pieces on the western front, which is quite managable.
The Italian mobilisation in 1915 needs to be slowed down considerably (fewer infantry corps and maybe just 1 HQ in early 1915 and a second one towards the end of the year)
The Ialians already barely have enough troops to both form a solid line and garrison its eastern coast. Reducing those numbers will make it extremely vulnerable to a spoiling attack launched as soon is war is declared.
introduce major Gallipoli event to force the Ottomans to maintain their strength near Constantinople and address the “micro-landings” and artillery issues.
Gallipoli is a disaster waiting to happen. I don't see anyone electing to take this option in a DE, unless you gain a ton of free stuff. And if so, a player would just pick it, then immediately transport them out as soon as practicable.
make USA entry into the war in 1917 almost a certainty
The 1914 Triple Alliance scenario does have this! That being said, given the current balance for the 1914 Call to Arms scenario, this would swing the advantage way too far in the Entente's favour I think. This is balanced out in the Triple Alliance scenario since Italy is on the opposite side.
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