Our apartment has perfect localization (10 minutes walk to Wawel Castle). Kazimierz is Kraków party district ;) there are pubs, clubs, restaurants on every corner.
Flat is brand new and although it is in an old house (after renovation) has all the facilities. Rollaway bed downstairs is surprisingly comfortable if you need additional place to sleep.
Oh and you have that awesome garden which is shared space for all residents. Just take sunbed and chill :)