I would like to suggest to add vector tools to Sketchbook to extend the possibilities of Sketchbook, especially for professional designers. At the moment the target group seems to be concept artists and amateur painters (maybe comic artists too), but not professional media designers. In this use case you start to design something and you usually export it (the geometry) for web or to continue your work in another software or with a 3D printer etc. For this workflow vector based graphics are essential.
Autodesk already had Sketchbook Designer for this but it's no longer available and there aren't many good vector based drawing applications. So, I'm suggesting to integrate the functions from Sketchbook Designer in the current Sketchbook Pro.
I know this is a big step, but maybe it is possible and I thing a lot of user would appreciate that.
Maybe the concept of Personas (from Affinity Designer and Photo) is something you should consider to keep the UI clean and handy for both types of users, the artists and the media designer.