It currently look like this;
the upper button was suppose to load the current state of " checkBoxUseCurve" of a selected brush.
[its not working XD very well]
the rest are toggle buttons;
So far the issues im trying to fix;
It does not work properly when you just open app krita.
— It toggles the icon in the button but the check box is not toggling.
— it starts working after opening the brushpreseteditor and pressing one of the button to see it uncheck once. after that it works with the rest of the brushes without opening the brush editor
—there are times the checkboxusecurve is toggled uncheck but pressure is not turning off / with or without brush editor open.
As noted in your code , for some times it does not seem to select the view.
It works so far for my need. 
Edit: still investigating XD i got too invested to this. I feel like im missing some sort of an enter or click trigger.
As i read it seems that the .select and selectCurrentIndex only transfer the selection but dont trigger the click signal. it seems the click signal is the one that switches the view.
Slowly learning pyqt.