I find Qt and JavaFX applications are both generally nice to use. Of course anybody can write a bad application with any framework, so the framework alone won't

I find Qt and JavaFX applications are both generally nice to use. Of course anybody can write a bad application with any framework, so the framework alone won't save you. While I only have firsthand experience developing with JavaFX, if I were doing something in C++ or Python I'd reach for Qt.