Initially, Austria mobilized trade. As Austria's trading prowess improved though, she was turned away from many COTs. However, by that time, Austria has a fairly sizeable territory under her control. Thus, production and tax income continued to fuel the economic engine admirably. All of Austria's missionary activity had the impact of accelerating Austria's economic and military growth, since less money had to be invested towards the maintaining of stability over the long run.
A key decision was made by Austria's leaders as to the best strategy to extend Catholicism across Europe. Austria could have turned inwards and concentrated solely on converting all her populace to Catholicism or she could have turned outward to bring the greatest number under Catholic rule. The latter was chosen, since Austria's astute leaders realized that political/economic control would ultimately lead to adoption of Catholicism among later generations.
The good relations which Austria enjoyed with her Catholic neighbors both allied and un-allied allowed Austria to mobilize against those who had drifted away from the True Faith with a singleness of purpose.
Over a couple of centuries Austria offered to vassalize Poland knowing that in asorbing Poland, Austria would be able to bring much greater prosperity to the Polish subjects while assisting Poland to find a greater purity of faith. But the Poles continued to value their independence above all else. Poland proved to a loyal ally through the years and the Austrian leadership never contemplated going further with the idea of a Greater Austria in Central Europe beyond making diplomatic overtures.
A final footnote: In the final years, the Austrian economy was practically double the size of her European contemporaries. This is probably an understatement of the case, since Austria had brought inflation down to 0% whereas others were struggling with inflation as high as 50%.
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This game was interesting for me. It demonstrated that great power could be achieved while playing a largely peaceful game. It also made it clear to me that economics is the key to all success. You can buy technology, friends, allies, armies, and conversions if you are filthy rich.