AlwaysOn AG versus FCI
In general, FCI is more beneficial compared to AG because of various reasons already mentioned above. Of course, 2-node FCI is completely great but should not be built on top of storage spaces direct since S2D is known to be problematic in less than 4 nodes deployments (source).

For Azure, I would rather stick to a VSAN that is designed to work in 2 or 3 nodes scenarios like (example).

Here is a bit more information on FCI vs AG that you might find useful too