Better Air Force in terms of numbers and types of assets, of course IAF.
Better Air Force in terms of external support from Russia and other Western Countries, IAF.
Better Air Force in terms of training and tactics, PAF.
If IAF is strecthed along the north eastern theatre by PLAAF, the first point will not be relevant.. because on western border, the ratio of assets will be almost 1:1.. after that the quality and tactics will take hold. Even if PLAAF doesn't attack, but just threaten to attack.. and land half of its strength on Indian northern border, PAF can easily take on IAF challenge.
However, if it's one to one without any external support, in the short term, PAF can inflict moderate damages on IAF.. In the long run though, if IAF is able to destroy air strips, and other infrastructure, and air borne AWACS somehow (and there's a chance it can), PAF will be facing a serious disadvantage. The depth of Pakistan is a problem, while for Indian AWACS, the depth is not a problem at all.
In short, a limited short time skirmish will benefit Pakistan immensely, and world has seen that on 27th, however, if the war continues across the whole LoC and International border, IAF may overcome PAF.
This is why, Pakistan will not lose any opportunity presented during the next Sino-Indian war. After Taliban take over Afghanistan, the depth issue will also be solved.
India had a very good opportunity to attack Pakistan after 27th Feb, but it chickened out. You can also say that Pakistan played her cards really well. The window of capturing AJK and GB is now closed.. At this very moment, Indians are trying hard to address issues with China. For that, they have even agreed to let go of 1000 sq kms.. so that in case of a war with Pakistan, there's limited chances of Chinese attack. India also wants PLA and PLAAF to go back to earlier positions (even she doesn't care about the 1000 sq kms for now to achieve this).. so that IA and IAF can again enjoy the numeric advantage against Pakistan and try to capture some part of AJK/ GB whenever they get a slightest opportunity.
With due respect, I do not agree with your assertion that PAF assets are comparatively lesser than IAF.
On papers yes, they may have greater number of assets, but how many are serviceable, its million dollar question!!!
It is a known fact that IAF assets maintenance statistics is very poor. Serviceability and reliability ratios are less than 50%. Turn around of almost all the assets is more than 1.5 hours.
Pilot to aircraft ratio is less than 1
Whereas PAF serviceability and reliability ratios are better than many US bases. Turn around time for almost all aircraft is 30 minutes or less.
PAF is having pilot to aircraft ratio 2:1.
Hence PAF can generate large number of sorties 24/7.
More number of sorties means more offensive and defensive missions.
Furthermore, critical spares requirement and armament replenishment can be satisfied either locally or from Turkey and China.
The only problem which PAF may face is the availability of aviation fuel if the war stretches to more than a month.
Though PAF assets are considered having lesser capable, but actual facts are quite surprising. These assets are strategically configured to achieve the required missions keeping in view the IAF and Indian Air Defense capabilities.
Considering the training, tactical skills of pilots, availability of competent weapon systems and their allied force multipliers, it appears that PAF can take out all air assets, missiles, artillery units and air defense assets deployed within 1000 km from Pakistani borders in less than 36 to 72 hours after the start of conflict.
As you stated that India had the opportunity to attack GB and AJK due to numerical advantage in air and ground assets, but India did not. You stated the reason that India chickened out. Here I disagree. After 27 Feb, Indian hindutva leaders were all out to take revenge, but they could not take this initiative due to the ground realities ie non-availability of enough serviceable assets for this invasion.
That is why, these idiots went berserk to buy weapons form Russia, US, Israel and France.
The new weapons which they are receiving now will be fully integrated not before 2021-22. At present these weapons are of lesser threat as their full capabilities could not be exploited.