IPL might rejuvenate many players like Hardik, Dhawan, Chahar, Bhuvi etc which is why it might help many returning players in a big way.
Sanju Samson is one player who has performed exceptionally well in the IPL, but failed to do the same while playing for the senior side. As you pointed out, there are others such as Hardik and Dhawan, but they are like regulars in the national side. This edition of the IPL may offer great opportunities for players such as Navdeep Saini, Khaleel Ahmed.etc to cement their place in the senior side. Anyway, there is extreme competition for the limited number of available slots.
Sanju Samson is interesting cricketer and looks strong when batting but he has big problem - Consistency- even in the IPL, Most of times he gives below average performance (Opposite to his talent and expectations) and sometime out of nowhere he gets his team out from the crisis.
Khaleel is disappointing example for everyone so far, Management still backing him because he's left arm bowler as left arm provides different angle to batsmen in cricket, otherwise he can't make into zonal teams.
@everyone : Guys, can we move this discussion into T-20 thread? . Discussing T-20 and IPL selection in Test Thread seems odd IMO.