Currently only Views can be hosted in the MainContent. If users can host Pages the RadSideDrawer could be used as root navigation component. This will allow customers to define the RadSideDrawer once throughout the application.
A few things are missing from Xamarin RadSideDrawer. Here's some we found in Android docs, unavailable on Xamarin Forms (and currently causing us issues that require rethinking the app's workflow, as we really needed a drawer that stays fully locked and cannot be dismissed by the user).