I think when there are only 4 contestants left, there should be a classical singing round to test the real musical knowledge and talent. I have a feeling that final 2 standing would be Hema and Nihira. (though I love Himani's style of singing as well!!)
May be songs get picked by the mentor of different team or may be there are real judges (peole with strong music knowledge) for that round.
I think that will be the best way to make sure that the deserving person wins the contest.
Is there going to be one male and one female winner or just one winner?