We have just published the v1.0.0 of the Office 365 CLI with even more commands for managing Office 365 tenants on any platform.
Docker images offer you great flexibility for building SharePoint Framework solutions. To truly benefit of Docker, you should include your own tools.
Using SharePoint Framework packages, you can request access to APIs secured with Azure AD. But there is also another way to configure additional permissions
Using the Microsoft Graph you can easily create a new Office 365 Group, that is, until you try to set its logo.
Why should you register SharePoint Framework extensions programmatically and did you know that you can deploy your solution to SharePoint directly from npm?