I would refrain from giving specific advice but please consider this general advice. Hope you find it helpful.
Given you are a HNI.
1. Keep all banks non branded core card if they cost you below ₹600 Annual. {For offers plus every brand have automatic insurance for card holder}
2. keep atleast one card for each network.{Visa, master, rupay (assume Ammex as network itself, they have their own ecosystem)} They all have travel insurance, luggage theft assistance etc.
3. You can just buy lounge access at airport so don't get too carried away for this offering.
Only you know which is beneficial to you based on your emotional and usage pattern.
Good luck. hope this advice finds you well.