My bet would be focusing on things like a common interface for Object Storage (everyone is making their products S3 and DynamoDB protocol compatible already) pl

My bet would be focusing on things like a common interface for Object Storage (everyone is making their products S3 and DynamoDB protocol compatible already) plus a common interface for cloud API operations (creating / managing infrastructure). Those would go a long way. Then you can think about how compatible more niche services like the various message queues etc can be made.