Well, it was the Russian 1914 Offensives that caused the Germans to actually swing troops round to the East. They had anticipated the sleepy Russians to take a bit longer to get grinding. What if Russia doesn't really begin assaults in 1914, but waits for 1915?
This way, Germany is still pounding away at France and the BEF, and AH deals their sad little war with Italy. Maybe Russia does some minor fighting with Ottomans to keep the Allies from whining too much.
This will have the dual effect of the Germans pouring more and more men in the West, where the majority will be, where they will no doubt be making more gains than OTL, etc. So, when in 1915, the Russians do begin punching at Galicia and East Prussia, perhaps they meet with less resistance. I mean, they took Galicia easily enough, but maybe East Prussia loses a bit. OR they put much much more effort into toppling AH instead of going after Germany...
Germany then realizes that - while they have France on the ropes - little brother Austria is in danger, they swing troops about as OTL and by 1917 France is looking for peace, Britain can't carry the fight without France, and Russia is in a better position to bargain. Maybe they'll exit the war as 'victors' early like a reversed Brest-Litovsk. That is, AH is cut up with Russia getting some control - namely Galicia - and makes a deal with Germany where Germany gets some extra say-so in Austria and the borders stay the same. Or perhaps Russia proposes the treaty to demolish the AH to appease Russia, Italy, and Ottomans. And the Serbs, since they started it all.
With the Ottomans out of the war with Russia (maybe), they might end up seeking peace with the Allies, but it also might be too late. Italy, getting what they want from the cut up AH, leaves the war. Maybe. And thus Germany doesn't have to worry about propping up the AH, fighting the Russians, occupying and guarding huge swathes of countryside, and can ignore the Italians. Thus its mopping up of France as needed, and forcing the Brits to read the writing on the wall.
So: Attack later to allay CP fears; attack en masse on AH, the weaker partner; no total war demands, but realpolitik the Germans to a reasonable agreement.
Unlikely as all get out, but could happen.