jules m, our trip was 2013, so the very before times. And I'm not a foodie and don't tend to remember places to recommend, but I'll share what I do remember about food there. Of your itinerary, we mainly visited Warsaw, Krakow, and Zakopane. Note: all spellings approximate.
I dislike duck so cant help you there. I dont recall seeing a lot of craft brew, brew pubs, biergartens etc., mostly it seemed vodka was the main social drink. But the big cities were pretty cosmopolitan, so a lot of trendy bars and lots of international food (pizza, spaghetti, some Chinese, etc.). Some of the Poles and guides we met say that they dont really eat the traditional foods that often. As you might guess, its a cross between Russian and German - heavy and starchy.
Of course pierogi were everywhere, but they come in both sweet (blueberry!) and savory (mushrooms, saurkraut, meat). So try a variety and some places have cooking classes. Sausages we mostly saw as street food, along with zapiekanki (a kind of makeshift pizza) and, in Krakow, big soft pretzels. A place I do remember in both Krakow and Warsaw, was Krakowski Kredens, a deli with tons of sausages and other delicacies, and take away sandwiches. A common dish we saw on almost every menu was pork cutlets, sometimes with mushroom gravy. Carp and herring are common. Stuffed cabbage (golumbki) and mushroom soup are very traditional. Cream cake was popular dessert, along with other tortes and tarts. One item that makes a good light meal is nalesniki, which are much like thick crepes, with both savory and sweet options. InYourPocket guides was really helpful to locate places.
In Kaszimerz, go to Szeroka Street, which is really a square. it is (was?) lined with nice restaurants, with hawkers standing outside showing you the menus and inviting you inside. A couple of Jewish-Israeli and Jewish-Yiddish restaurants were there when we were there and I think the Yiddish one has (had) klezmer music. It was featured in one of Rick's videos. At the end of the square is an old synagogue used a s museum, and was a setting in Schindler's List.
The only place we came across traditional music was in Zakopane where we ate in a place that had music and dancers from the Goral (mountain people) traditions. Locals told us that most people listen to Europop - the polka-flavored things is mostly for tourists. Zakopane also has a big craft/food market at the foot of the mountain, where you can buy "ears" of the local sheep cheese for sampling.
The one traditional food item I hesitate to mention is the smalec. This translates as lard, used as a spread on bread like butter. Its tastier, more like bacon fat with bits of meat. Some people turn up their noses, but if you think about it, butter is animal fat too.