@ Steven....One of the traveling delights in the summer is that one may come upon a daytime outdoor performance (Konzert im Freien) by an orchester if you're lucky. I saw that as my lucky day. After finishing with Beethoven's 5th, Simon posed the question, more than once, (in German) to the audience which was clapping for an encore, what can one play as an encore to Beethoven? Obviously, it had to be something light. So, they played an overture by Mozart, the Magic Flute. The Berlin Philharmonic came to Calif once, at least , when I was following this sort of news in the 1970s and early '80s, not to SF or even LA proper but to Pasedena in 1980 or '81. Tickets were expensive, for me too. A good friend of mine went to two of the concerts, got blasted later by the Mrs for having spent that much money, but he said seeing them play was like no other orchester he had ever seen before.
On your Vienna trip in Oct: go out to the Zentral Friedhof (the main cemetery) not only to see where a good number of the composers' graves, (Strauss, Beethoven, Schubert, etc) but also the WW1 section, way in the back, ie, be prepared to do some walking tracking down the WW1 section...grim, poignant. Those opening battles in August and Sept 1914 destroyed the flower of the Monarchy's junior officer and non-commissioned officer corps, something from which the Austro-Hungarian Army never recovered.