Best approach to set a itemdelegate strategy?

I have a custom table/model schema in which I want to apply a 'multi delegates' selection.
(in other words each cell can be any 15 'delegates types' I have.

I set this 'type' using index.data(QT::UserRole).
So, when custom_model.data event with role=DisplayRole is trigered I can to know what type I have to show (the createeditor function of my delegate).
As there is not a set_itemdelegate(row,col) function... Is this approach the best I can do ?
What do you think about it ?
Thanks