Well, S-400 will be deployed in formations that it will create a no fly zone in Pak when needed, most of your aircraft, cruise missiles and Nasr will be shot down in your own territory during war-time. Let alone, once you get closer to the border, there will be plenty of Akash, Spyder and Barak-SAMs. In conventional terms Nasr is no match for the Pinaka which has a similar range 40-60 km and we can fire 12 missiles from a launcher in under 50 seconds, a battery has 6 such launchers and able to deploy 72 missiles towards any target, together they can neutralize an area of roughly 3.9 sq km. We just ordered another 6 regiments of this puppy. We are also ramping up production to over 5000 missiles a year.
Together with Brahmos which has no counter and over 4 regiments ordered, there is plenty of conventional power that India can deploy that Pak can't defend itself against, your ground troops will be massacred, there are no defenses that can withstand the onslaught of 1-2 Strike corps and 3-4 Pivot corps.
Over the last many wars, your folk couldn't really do much, you got your *** handed out to you during all wars. You did have the advantage that comes from starting a war but quite quickly you were taught a lesson.
NASR is a shitty weapon that has no advantage on the battlefield, most of them will be shot down by the S-400 and if Pak is stupid enough to bring nukes well then its goodbye neighbor. India will still launch its nukes on a strategic strike. Its quite simple really, bring nukes to the table and all gloves are off, the retaliation will be massive and completely punitive. All the while the S-400 along with PAD/AAD (being deployed in key cities now) will counter all missiles fired at us since the volumes being ordered allow for us to expense multiple counters for every missile being fired.