It is necessary to allow the private ArcGIS Online contents to be added BIM360 Esri card(Dashboard).
For now, the public contents can be added on BIM360, but private contents can be only added through using a temporary token.
The workaround is addressed here: How to load Scene Layers from ArcGIS Online Contents to BIM360?
If it is possible for customers to add ArcGIS Online contents on BIM360, he or she would like to keep using the Esri Online services.
If the customer can add private contents that are credential to the organizations, it will highly increase the productivity of his work.
There are bunch of other apps that can be added on BIM360. Esri should have some specialty and extend the compatibility between itself and BIM360, because there are so many advertisements on their high compatibility. I believe there is lack of resources and guidance for working between AutoCAD/BM360 and Esri products in despite of the advertisement.