Osijek, Croatia. University city. Thriving tech hub. Close to 4 major international airports (Budapest, Zagreb, Belgrade, Timisoara). Low rents. Low cost of living. Decent food. Very walkable. English is widely spoken.

There are many other cities all over Central and Eastern Europe like this. Other options are Novi Sad in Serbia, Szeged in Hungary, Brno in Czech Republic (the major tech hub), Timisoara in Romania (same), Lviv in Ukraine, Krakow in Poland, Tartu in Estonia.