Sivabalan,
IMHO the role of a functional consultant will become even more important for those, who can combine SAP implementation talent with Business knowledge and even more important practical Business experience.
The SAP Activate methodology Guided Configuration in S/4HANA replacing SAP ASAP methodology focuses on the importance of a customer to adapt more quickly to changing business conditions rather than long-running Blueprint exercises which typically set a process in concrete as it is so "overcooked" that it can not be changed anymore.
S/4HANA sets the foundation for agile innovations a system of engagement rather than the traditional legacy system of record approach, which focuses on the past (recorded history). More details in here:
https://en.wikipedia.org/wiki/Systems_of_Engagement.
thank you
erich