Yes, I think Krakow was probably the nicest surprise of my tour; with the lovely, crumbling buildings and churches of the old town. I even preferred it to Prague.
I went to Auschwitz partly because my ancestors were Jewish. I did my M.A. dissertation on Anti-Semitism and, in my research, found people with my name who were killed there. So when I visited I felt it was all the more meaningful for me. I really appreciated the fact that visitors can just walk around freely. In doing so I walked for perhaps five hours and was astonished at the scale of the place.
I, too, am interested in the pronunciation thing and wanted to be able to pronounce it like local people, but when I listened to people talking around me, I heard Krakow, Krakov and, even, Krakovia, so I'm still not certain as to local pronunciation!
Next year I might go back to Poland and perhaps Zakopane. I'm sure you know it's often referred to as the Polish Switzerland - surely Switzerlandski would be better! - but I'd welcome any other suggestions for visits that you might have.
In Prague, the Welcome Hostel Hlavcova, is nice and quiet and is very near the river and metro. It's just 20 safe minutes walk from the old town and a few weeks ago I had a single room for 17 GBP a night. I booked it through rail.shop/hostelworld
and I think there's a discount for booking on-line.
Have a great trip.
All the best.