The disclosure relates in some aspects to the use of host metadata by a controller of a data storage device, such as the controller of a solid state device (SSD) having non-volatile memory (NVM) arrays that is coupled to a host device. In some aspects, the controller parses metadata within host commands to extract relevant hints and then correlates the hints with actual host device behavior. If the controller finds a strong correlation between the metadata hints and the host behavior, the hints are used for command storage optimization. Later, if there ceases to be a strong correlation between the hints and the host behavior, hint-based storage optimization may be suspended. In other aspects, the controller uses metadata to provide for virtual or expanded write streams. In still other aspects, the controller and the host device negotiate a structure for metadata during an initialization phase.