In delhi I have used spectra, siti, hathway, mtnl in last 5 years and all of them had worse latency compared to airtel.
Singapore server will never go below 90ms on these ISP whereas on airtel it won't go above 80ms.
NA servers are worse on airtel but EUNE and SEA servers are better.
I have heard good things about ACT fibernet so maybe try it if they are in your area.