thanks for your reply, but unfortunately AlwaysOn is not the same as a "real" FCI, in my opinion AlwaysOn is like a narrow gauge cluster without the need for shared storage.
An FCI covers everything about the SQL instance - databases, logins, certificates, policies, agent jobs, and more. Whether you have two databases or hundred databases, they will all go together. An AvailabilityGroup will only fail over the data in the databases that are in the group. You must separately manage everything else. The more replicas you add, the more complex management becomes.
maybe this is one reason I'm considering to move away from VMware to Hyper-V because there are snapshot capable shared VHDX available