The need of a larger aircraft arises out of neccessity. If you don't like what is available---then you have to build up on what you have and what you believe works---.
A 25% larger JF17 would be the most optimal size---which could carry a load of upto and around 7-8 K kgs---good sized radar in the nose cone---has a good loiter time.
Actually 25% larger aircraft was the " original design ".
And why would Kamra do it---why not the same place that manufactured the JF17---. I think that it maybe upto a 100 million project---.
Pakistani perception is that as the Swedes are relying on the Grippen to take on the Russian air force---why can't the Paf take on the opponent with an aircraft of similar capabilities to the Gripen---the JF17.
They say---both Pakistan and sweden are facing similar kinds of aircraft in combat.
So---for them---the JF17 must do it all---because the Grippen will supposedly do the same.
What they don't realize and don't want to acknowledge and admit is that behind Sweden---stands the might of the Nato air battle group which is an ear shot away and won't need any invitation to jump right into the fray with all its might.
For pakistan---there is no such saviour at hand.
I would say again that the JF17 is an excellent COMPLIMENTARY aircraft---.
It is a perfect ' primary ' aircraft for many a nation---but not for Pakistan---which faces an opponent with 3 times the numbers of medium to heavy aircraft.
If Paf does not want the J10 and does not want to spend for a larger JF17 and does not like anything else---then it needs to get the JH7B---.
To say that JF-17 is a complimentary combat aircraft for Pakistan Air Force, is an inaccurate assessment. Air combat consists of many variables, involves a plethora of conditions which have a direct impact on the performance, capability and victory or defeat in a fight.
If one were to assess the JF-17 Thunder, in context of Pakistan Air Force, within the air space of Pakistan. Taking into account the geographical length and breadth of Pakistan. It is fair to say that the size and endurance of the JF-17 Thunder is sufficient to fulfill it's role as a combat aircraft, defending Pakistan's air space.
JF-17s primary role must have been envisaged as Air Defense and Air Superiority fighter, over Pakistan's air space. The aircraft provides Pakistan Air Force with a very decent capability, at a cost which affordable to the country. Needless to say, that this is Pakistan's first foray into combat aircraft manufacturing. As such, JF-17 Thunder is an excellent first venture. Providing Pakistan Air Force with a vast canvas to further tweek and develop this aircraft.
There is an enormous potential in working with our Chinese partners to further define JF-17 Thunder's role and capabilities. In terms of avionics, radars, air-to-air missiles and self-defense suite. These are areas where Pakistan has the potential to establish a home grown industry which can customize the Thunder further into Pakistan specific aircraft. In the same breath, also allow development of software which will interface with new capabilities that are in development for JF-17 Thunders.
25% increase in surface area for Thunders is a likely possibility. If the requirements are identified by Pakistan Air Force, in the future. It hinges on the prospects of whether the JF-17 Thunders are envisaged to carry out deep-strike missions. For which range would directly depend on the quantity of fuel an aircraft can carry. Another need to increase the surface area of the JF-17 Thunders, is to increase number of weapons' stations, in order to carry heavier or increased number of stand-off weapons.
At present, JF-17 requires prioritized development. Specifically, to seek out means to increase the efficiency and endurance of its power-plant. Fuel efficiency in a power-plant, without sacrificing thrust, is one avenue that Pakistan Air Force ought to be exploring. As the saying goes, "A car is only as good as it's engine." So to with combat aircraft, where the power-plant is one of the major components that determines the aircraft's capability.
In my opinion, improved efficiency and performance of power-plant is of greater importance for JF-17 Thunders, than an increase surface area. It is a far better approach in the further development of the aircraft, at a cost which is more feasible and realistic, for Pakistan.
As for J-10s, and why Pakistan Air Force is not moving forward with its acquisition of the aircraft. Only argument to support this would be a financial one. As it is quite apparent that a lot of resources have been poured into the development of the JF-17 Thunders. Ideally, J-10s would be the perfect primary combat aircraft along with JF-17 Thunders. However, we do not live in an ideal world, nor does Pakistan have the luxury of unlimited resources to acquire a new type of combat aircraft, while also developing and manufacturing one on its own.
J-10s are a prime example of Chinese aeronautical engineering. It is a magnificent combat aircraft with tremendous capabilities. And if circumstances were to change economically for Pakistan. The J-10s would be their first choice as high-end fighter.