Krakow is pretty much THE place for tourist visiting Poland if they come here to see some history. Unfortunately I was there maybe two times for pleasure - going there for business is completly different story
Best I can do is to direct you to the official city website:
http://www.krakow.pl/en/?chl=ENWhat I didn't saw on that website is the
Museum of Aviation, which have some pretty interesting exhibits, like part of Goering's World War I collection, Viggen, Starfighter, interesting collection of MiGs etc. etc.
Oh, and an F-5 that was acquired in Vietnam some time ago... still have bullet wound in his wing
Now when it comes to smoking, for the past few months there were some changes in legislations and smoking in public places is considered prohibited... though for many people "old habits die hard"
and you can still see some people smoke, and law enforcement have other things to worry about than reminding people to care for their addiction in their own homes
Seriously though, if you really have to, you can try and the worst case scenario is being lectured about the current laws.
As for hand rolled cigarettes, those are quite uncommon here, and most people smoke fabricated ones as they are still cheaper than anywhere in Shengen countries, therefore yes, people will think your're smoking a joint
As a foreigner you will be treated rather lightly when it comes to breaking those kind of laws, and as Israeli while in Oświęcim (Auschwitz / אָשפּיצין) you will probably go with a group everywhere and will not be bothered by anyone, it's an unwritten rule.
Enjoy your visit, and if you have any other questions just ask.