Well O.K .. Lets cut it down to 250!
So approximately 250 fighter aircrafts loaded with BVRs and supported by AWACS/AEW&C will be facing Indian thrust into Pakistan. In the Pakistani airspace , we will have
numerical advantage over IAF fighters. Add medium range SAMs and electronic warfare in the picture. PAF can effectively thwart IAF from gaining any advantage over the battle field. This is the main purpose of the force. PAF's offensive role will be very limited. Pakistan Army's Strategic Missile Command will carry out ballistic and cruise missile strikes all over India , until the cease fire is called !
Don't forget about stand-off weapons like Ra'ad that Pakistan Air Force carries. PAF doesn't need to go deep inside Indian territory. It can devastate Indian forward air bases by using its stand-off weapons effectively. Also , upto 15-20 days , Pakistan can hold
full-thrust all out Indian invasion of its land. Remember , there would be thousands of tanks , aircrafts , soldiers , submarines , ships , artillery etc that would be battling out Indian forces in the sea , land, and air ...so we are good. Until then (first 15-20 days) , Pakistan would have inflicted some serious damage on Indian Forces , Indian cities , Indian infrastructure , and specially Indian economy. Indians won't even think of taking the war that far. A week is the MAXIMUM Indians would fight before the cease fire would be called by both sides. Indians won't risk crossing Pakistan's nuclear threshold by taking the war to more than 15 days.
So we are good against Indian aggression ( a thing they won't even dare to do in the first place). The only most-important thing we need is long range effective radar and SAM network....so we can monitor and aim at Indian Air Force well within Indian border. In this way , their "Cold-Start" and "Surgical Strike" initiative will be effectively taken out by Pakistan Air Force and Pakistan Army!
Chill ....