Wow just wow, you should be in top ranks of IAF and making strategies for them. If we go by your logic if numerical advantage means so much what happens on 27th February 2019, cat got hold of 1.4billion tongues.
With this new addition Pakistan Air force is formidable force and will give IAF run for what its worth (not much). Since last 70 years not one inch of Western border was pushed by 1.4billion. So I would suggest keep your backward theory to yourself and keep justifying yourself with your 1.4bill numerical advantage.
It's really about styles of warfare; China never really had warrior elites beyond the Zhou dynasty chariot archers, or perhaps Northern and Southern Dynasties where heavy cataphracts made a major difference.
In European and Japanese warfare, elites (hoplites, legions, knights, samurai) mattered a lot, because superior training, armament, and armor allowed them to defeat forces many times their size. In Chinese warfare, in contrast, the strength of the missile arm (crossbows) meant that elites were often relatively useless or consigned to a combined arms role because they by themselves could not achieve the same efficiencies as they could in European warfare.
Now, which is superior? It's a matter of circumstance. The Chinese were imperialists, but never "great" imperialists, given that they got kicked out of Vietnam and Korea, in the former case, repeatedly. That's to do precisely with the style of warfare; focusing on elites and quality over quantity also ended up reducing your logistics train; if five crossbowmen were equal to one knight, the one knight might have higher upfront costs (training, equipment), but lower sustainment costs (the knight needs food for one and food for the horse). That makes the knight more effective in expeditionary warfare, but less so in full-scale attritional warfare.
As a counterexample of where "numbers" beat "quality", look at World War II's Eastern Front. Pound for pound, the Red Army could never match the Wehrmacht; they usually took outsize casualties and relied on numerical superiority (which isn't a bad thing; I've stated on Leftypol the moral superiority of levee-en-masse and what a Communist militarism should look like). However, the Wehrmacht was ground down. Their well-trained and well-experienced forces ended up getting attrited down by the Red Army, until the Wehrmacht was forced to conscript old men and children just to slow the Russians down.
So, what we know is that in a standard "imperialist" action, elites beat masses due to a lower logistical requirement, and in a full-scale attritional war, masses beat elites because the logistics stop mattering.
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In the Pakistani case, relations with Iran are fairly good, the Taliban Afghans are virtually a creation of the Pakistani intelligence services, and China is an "all-weather friend". The case where Pakistan COULD expect to face both large-scale warfare and limited wars would be with India.
In this case, in the event of large-scale warfare, Pakistani forces provide a deterrent function, but ultimately it comes down to nuclear weapons as deterrence, since Pakistan can get overrun by Indian numbers relatively easily. A further point to note is the probability of Chinese intervention; i.e, in a full-scale war between Pakistan and India, China is likely to get involved, at least in terms of transferring arms to Pakistan, and at most moving to intervene by itself, so Pakistani conventional deterrence doesn't need to be that strong.
Where an upgraded J-10 is more interesting, though, is in cases of limited warfare, such as Kargil etc.
In a limited war, both sides are trying to avoid escalation, and deploying numerically superior forces IS a form of escalation, when both sides have substantial military forces and nukes to boot. On the other hand, qualitatively superior forces present a way to cheat; it doesn't look like escalation if you use more "capable" assets; it's still a "fair" fight and you can always call foul and escalate (and both India and Pakistan are nuclear states).
That is where I think upgrading the J-10 comes into play for export to Pakistan and other countries. For the PLAAF itself, the J-10 has been relegated to a training tool and cannon fodder; the PLAAF should be running either J-20s for air superiority with Sinoflankers to do strike roles, or a combination of J-20s for air superiority and J-31/35s for strike / air superiority roles. But for other countries, an upgraded J-10 represents a substantial improvement in combat capability; i.e, it represents more sophisticated electronics than what the Russians sell (MiG-35 doesn't count; the AESA is previous generation and doesn't have enough T/R modules), has 4-4.5th generation maneuverability courtesy its canard-delta layout, and compared to European options, it is substantially cheaper.
If you're thinking TVC won't make an export J-10 more marketable, consider the Su-30MKMs. China is special in that the Su-30MKKs had no TVC; many other Su-30MK marks have TVC. Why? Because most of the Su-30 purchasers are either tinpot populist dictatorships, where post-stall maneuvering (hey, this can do what the Su-35/F-22 can do!) can impress the incompetents in charge, or populist democracies, where post-stall maneuvering pleases the fanboys that make up part of the electorate (hey, our TVC J-10s can do what the Su-35 / F-22 can do!).
At the very least, TVC should be an option for export J-10s. If you look at the F119 vs the F135, they cost essentially the same amount of money, so TVC won't be an excessively high increase in the per-unit costs of J-10 export versions. It matters a lot because when the tinpot generals ask whether they want to buy a J-10 or a MiG-35 (roughly in the same class), the lack of TVC might be a selling point because procurement is not made on purely strategic considerations, but also on political considerations.
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End of the day, I'll admit the reason I want TVC in export J-10s is purely for fanboy reasons. The best amphibious tank in the world, mind you, happens to be Chinese, because amphibious tanks are out of fashion and no one else has a late-generation or upgraded amphibious tank. The best light tank in the world, likewise, happens to be Chinese, because barring the new American light tank program, no one else is bothering to develop late-model light tanks; they're all IFVs instead. Likewise, if Chengdu / AVIC wants to do it, the best 4.5th generation fighter could be Chinese, simply because everyone else is working on 5th and 6th generation aircraft, and the Europeans won't upgrade Eurofighter with EJ220 TVC, or even the AMK set-up that makes it superior WVR to Rafale.
