IMO we need to build a lot more frigates and corvettes than the ones currently planned. If porkis end up building even half of these, it will be a much bigger headache than currently. Not sure why IN is not ordering more P17As or even starting a P17B with some more refinements, such as bringing back 2 hangars, upgrading the radar etc. There is simply too large of a gap between the delivery of P17As and NGF
NGF is likely going to be an evolution of the P17A design rather than a completely revolutionary design. Also, look at the pace at which MDL and GRSE are building them, INS Nilgiri is pretty much ready to head out for sea trials by mid 2022 followed by INS Himgiri.
Not only this another 4 improved Talwar class frigates are going to join the fleet by 2026-27.
So, IN will have added 11 new frigates to their fleet by 2026-27, not a small number by any means.
Those Shivaliks, Nilgiris are pretty much mini destroyers given their displacement.
The main radar and air surveillance radars and their weaponry are pretty much at the cutting edge of what is available on the market.
So it is better to wait for newer technologies to emerge rather than hurry just to bulk up on nos and spend time and money to upgrade them later.