The outcome of a few conflicts could have been slightly different, not only the war of the Austrian Succession, but also the war of the Polish succession, the war of the Quadruple Alliance and the Austro-Turkish war.
A stronger Austria in the war of the Quadruple Alliance might have prevented the duchy of Parma passing to a cadet branch of the Spanish Bourbons.
In the war of the Polish Succession Austria was forced to fight on the defensive and Milan, Naples and Sicily were seized by their enemies no to mention that the duchy of an ally, Lorraine, was occupied by France. Later they eventually lost the kingdoms of Naples and Sicily in exchange for Parma & Piacenza. Also their ally was forced to trade Lorraine for Tuscany.
Now Lorraine might still end up occupied and due to the lack of naval abilities Naples and Sicily might still be lost, however in can see them defending Milan much better, which is closer to their core. I can even see Austria gaining those bits of the duchy of Milan, which after the war of the Spanish Succession went to Savoy.
A stronger Austria would also be even more dominant in the Balkans and may end up also keeping territories, which IOTL they only kept a while. In other words it might prevent the OTL treaty of Belgrade (1739) between Austria and the Ottoman Empire, where Austria lost Serbia, the Southern Banat, Northern Bosnia and Oltenia.
IOTL Austria had to cede Silesia and Parma, Piacenza & Guastella and had to return and restore the duchy of Modena and the Republic of Genua.
Now a stronger Austria could definetely fight for a Status Quo Ante Bellum, so no territorial loss this time, but they might still be required to restore Modena and Genua.
Another result of this is a weaker Prussia and worsened Austro-Prussian relations, Austria probably ends up closer to Poland-Lithuania-Saxony and thus no real Polish partitions TTL, though Poland might lose some territories. Austria might be interested in the Polish enclaves in Hungary, but other than that Austria might prefer Poland as an ally. Russia could very well end up seizing the lands they gained in the first and second partition treaty and Prussia-Brandenburg could seize Polish Prussia, but not more (and probably only when in the right alliance).