I think you will find Qt very easy to work with.

I have, myself, not yet started to develop anything for Sailfish but I have been using Qt/ QtCreator to develop various PC applications for a number of years.

Regarding Sailfish/Qt/Silica I think you should have look here for a start:
https://sailfishos.org/sailfish-sili...roduction.html
https://sailfishos.org/sailfish-silica/
https://sailfishos.org/sailfish-sili...ilica-all.html

//j