How would the situation on the Balkans develop in this AT if by some means (eg. more "liberal" kaisers coming into succession) the Austria-Hungary had added a third royal entity, for Slavic peoples? So we still have Cisleitania and Transleitania, but the disputed territories of Dalmatia and Bosnia are used as a platform to form either Kingdom of Croatia or Dalmatia. I suppose that if it was brought into reality much earlier before the Balkan wars, then the economic dependency of the Serbian kingdom could be used to Habsburg's advantage, and instead of sparking the Pig war/Customs war, it would be seen as a way of effectively turning Serbia into a protectorate that could be later incorporated into the Empire. Montenegro, Macedonia and even historically Slavic lands of OTL Albania could be later absorbed on the premise of "protection of Balkan Slavs". We could even see Bulgaria coming even closer into Austro-Hungaro-Slav empire, first off because of dynastic ties to Saxe-Coburg-Gotha (who even ruled over Great Britain untill 1917) to the Habsburgs. Bulgaria probably wouldn't see annexation, but would be expanded greatly to match the Second Bulgarian empire, while being a proxy state of the Habsburgs, being used as a tool to further expand and exert their influence over the Balkans.What would be the destiny of Greece, being an orthodox brother of the Russians, but an strategic ally of the British, and how would the decaying Ottoman empire react to a new challenger approaching, and what would be the actions of the Serbian government incorporated into The Empire? Could there be a Great War of global scale spark out because of the bickering of three great powers jockeying for their part of the Balkan pie, or would the troubles be resolved on grand conferences or local scale wars? What would be the fate of the Italians, and who would rule the Adriatic sea? Could we even see the Austrians be the first ones to get their hands on the Ottoman Libya and the Khedavite of Egypt? Who knows.