Your air India flight will be first flight from base which means you will not be delayed, atleast on departure. Unless there is a thunderstorm in delhi happening at the moment you land, expect delays of not more than 10 min. In case of thinderstorm, should not be delayed more than 30-40 min unless you are really unlucky and have to be diverted. But then that applies to everyone.

You will be treated to a nice breakfast. On board so thats also a plus point.

I don't like traveling on the 737 , so spice is out for me. And on a 2 hour plus flight , I would take the IFE , even though I feel it's quite cheesy.

Plus you will land in terminal 3 with air India, and in terminal 1 with spice and indigo.