A few thoughts:
It took western countries about 3 years to build a dreadnought, Russia 6. Presumably in this game it will take, what, 4 months?
Cavalry: I think cavalry is rather badly treated in histories of the war. It was only in static trench warfare that they became ineffective. Otherwise, they still made a big contribution. My suggestion for cavalry:
They should be treated as mounted infantry. That is, during a battle, you can dismount your cavalry and they fight as standard infantry. Their main use, however, should be in pursuit: if your cavalry have not dismounted, then they may pursue retreating enemies. Basically this means giving each cavalry unit a “free” roll against retreating ground units. Especially useful in desert regions where tanks cannot operate. Like Turkey.
Tanks: Should only hit on 1 in defence, period. However, I think there is a good case for their effectiveness in attack to be based on a combined arms consideration:
Tank alone: hits on 2
Tank with infantry accompaniment: hits on 3
Tank with infantry & artillery: hits on 4
That is, each tank need an infantry and an artillery unit in the attack round to gain the respective bonuses.
Could even consider a further tank bonus for attacking aircraft, foreshadowing tactical developments in WWII.
This is a realistic depiction of tanks in combat, and avoids the horrific spectacle of
columns of turquoise Turkish tanks heading over the plateau of Anatolia, and scaling the peaks of the Caucasus before descending to take Russia in the rear.
Latest image of IL’s German units:
http://www.boardgamegeek.com/image/1528366/rivet-wars