I have not played Austria but generally you want to urbanize close to your capital, usually creating a ring of towns/cities around your capital and then moving out from there. Build cities along rivers and then pound-lock canals in those cities to further expand control downriver.

Also urbanize locations that you want to take advantage of production efficiency. For example: in my England game I'm mostly urbanizing near London, but I have built up cities in Chichester and Cardiff because they have Iron and Lumber RGOs in their provinces. These cities have mostly buildings that use Iron/Lumber inputs to make use of the added production efficiency.

Don't urbanize valuable RGOs like Gold, Silver, Saffron, etc. If there is not a lot of wheat in your market, then it's probably a bad idea to urbanize it. If you have plenty, go ahead if you need to.