I was thinking we maybe could also abstract the PyQt/PySide/PySide2, there is the qtpy package that could become interesting too some day...
I read about qtpy in the past but at this time it only supported PyQt4 and PySide. Does it also support PySide2 now?
+1 for not supporting multiply qt bindings. There are for sure some incompatible things in pyside, pyside2, pyqt4, pyqt5. Better to go for pyside2 only.
Even if we go for one Python binding only but if using qtpy reduces the code changes for the PySide <=> PySide2 migration or any future changes like the PySide3 migration for Qt6 then it might be worth to have a look at it.
It might be recommended
but it's not mandatory
. Last weekend I build PySide2 with Python2.7 using MSVC2013. MSVC2008 isn't an option anyway because since the merge of PartDesignNext we need C++11 features which the old compiler doesn't support. So, on Windows the minimum compiler version is MSVC2013.