Delhi Domestic T3 - 6 hours

[theglobalinvestor]

I will have about 6 hours layover at Delhi domestic T3 terminal. What is there to do? Which priority pass lounge do you recommend? I have pp on hdfc infinia which also allows guests if I remember correctly.

Is it worth upgrading to business class on air India to get access to the air India lounge?

Please advise. Haven't traveled through Delhi Airport much.

Thanks.