V2 setting system-wide configuration settings like fonts

[yoelk]

Is it necessary to specify the font for all of the text boxes in the app?
Or is it enough to set the text boxes containers' heights with sp()?
extra reading: http://kivy.org/docs/api-kivy.metrics.html

And if we decide we do need to set them explicitly, we'd need a central place to save all of these definitions, but where?
The top widget?
The system preferences?