Regarding the use of QML and QWidget

[bibuboy]

Hi guys,
I we are developing a web based software platform . The current plan for the current product development interface is archived with
With QMainWindow, QDockWidget achieve MainWindow and SubWindow.
All SubWindow achieve internal use QQuickView
<List Of Group & Thumbnail> window using QML's ListView Item realization (QML)
<Main View of Group> window with QQuickPaintedItem derived class (derived class) to achieve the Tree of QML Item structure to form (QML) All Item painting based on traditional painting method QPainter
<Special Edit View>, <Item Properties> window is to use QML's Quick Controls, Layout to form. (QML)
<Detail Structure> window with a TreeView Item to achieve. (QML)
Questions I have are

The above method can be seen as the best way to do? ? Is there a more reasonable alternative method? ?

The mix QML and Widget developers will instead lead to more complex its scalability is even more down?

Does not use the QML but in the traditional way to develop Widget then there will be any adverse situation? ? ?

Thanks a lot ,
Best Regards,
Biman