I know that this must be completely done to death by now, but how could France, Britain, Austria-Hungary, and the Ottomans face Germany and Russia? Would it even be possible with the reinsurance treaty? Would Germany even be willing to throw Austria to the wolves and buddy up with Russia or even possibly partition Austria-Hungary (which honestly makes the most sense to me for both sides-German parts of Austria to Germany; Russia get Slovakia, the Czech parts of Bohemia and Moravia, and Galicia; Romania gets most of Transylvania; Serbia the Southern Slav parts; Italy enough to wet their beaks; and Hungary into a rump state).
Of course this probably would erupt into a wider war, as France and Britain try to prevent the old man of Europe from being broken up and aggrandizing their neighbors. It would also mean that Russia now has only one direction to expand:Asia, something that the Brits want to prevent. Germany is now very strong and dangerous to both the British and French.