you got it correct - Intel vPro Essentials are based on ME FW 16.x or newer and includes new/updated/enhanced Intel Standard Manageability (ISM) feature (which is feature limited subset of Intel AMT HW manageability solution).
ME FW 16.x ISM enhancements are described at _Implementation_and_Reference_Guide/WordDocuments/intelamtrelease160architecture.htm
it adds WiFi support and Internet remote manageability with Intel EMA with added CIRA feature support.
HW KVM Redirection is not supported by ISM with any ME FW generation - you will need Intel vPro Enterprise or Intel vPro platform with ME FW 15.x or earlier (but ME FW 6.x or newer).
Links which David Benedict provided are valid for ME FW up to 15.x only where WiFi and CIRA was not supported, and Intel ISM was available only on desktop and workstation chipset platforms (not on mobile platforms).
rgds