Osaka or Kyoto or both.
Kyoto beautiful and interesting, touristy but still great. Must visit and stay central. Enjoy the culture and sights. Lots of food. Stay and visit around this station and this side of river. Kyoto-Kawaramachi Station
Osaka is big city life, but laid back fun friendly culture. Stay visit near here Dotonbori Glico Sign
2 full days in Kyoto, 1 day n night Osaka, depart Osaka airport if possible.