For owners of a Windows 10 tablet that supports a pen, like MS Surface Pro or Surface Book and even Surface Studio, it is good that Notion offers hand-writing input! This works very well.
The concern here is that the Notion application seems like it is in its core still a legacy Windows desktop application and doesn't support for the new usability features of Windows 10, specifically for tablet users.
The user interface in the recommended resolution of 3000 x 2000 on a Surface 10 - 13 inch screen is extremely small and unpleasant to use.
When you support hand-writing recognition in your product, it means you put yourself in direct competition with a product like StaffPad, which means that you are in competition of all the usability features which a true Windows 8+ app provides. I would strongly suggest that the development team convert notion into a true Windows 10 App.
The integration into Studio One plus all the other features is great - I would urge you to stay relevant in the market and keep on making Notion greater.