I think Gen 5 has many issues of costs and maintainability and may not be optimal. Till now we have had:
1. F-22, sounds great, great propaganda and marketing but known in the USAF as a hangar queen, due to over-engineering, over-complexity, RAM issues, etc. As few as 90 are combat capable and cost close to 70,000 USD per hour of flight.
2. F-35. A slow, overly complex, poorly maneuverable attack plane with short legs. Most expensive plane in history costing 1.5 trillion USD.
F22 does cost a lot but it has all the bells and whistles. US can afford the over complexity and over engineering and it's not like all that extra tech isn't helpful to them. F22 gave US an edge over all the other air forces on earth...an edge they have had for a long time and there's still hardly any fighter jet that can challenge that after all these decades. I'm not calling other jets like J20 inferior...it's just that their abilities are yet to be seen. So far at least on paper and what's available online...F22 is still the best fighter jet though very costly.
As for the hangar queen part...well I would just like to say that no one should doubt USA's defense capabilities. It's not like they can't resolve any issues should they come up. I think it's most likely due to the fact that F22 is hardly needed. In the Afghan war, there is no Air Force they are facing and no SAMs. For the Afghan war...they can literally do all they need to do with armed drones and F16s, F15s, and other 4th gen jets. So why would they spend extra to utilize F22s there?
Before this there was Iraq war where the F22 may have been needed due to Iraq having a lot better capabilities in terms of Air Force and air defense systems...but even in that case US quickly established its control over Iraqi airspace and F22 wasn't needed for much of the latter part of the war.
Then there is Syria, which is complicated with all the different warring parties and US isn't really fully involved there so F22 would be sparingly needed if at all. In short the F22 would only be needed in challenging well defended air spaces facing foes that have a good and proper Air Force. In absence of that US can just use other aircrafts which will do the job just as well at a lower cost...and hence hangar queen...but not due to a lack of capability on part of the US.
F35 had cost overruns bcuz it was to be provided to multiple partner countries that each had their own needs. On top of that Israel wanted its own avionics in Israeli F35s...and to complicate it further, they also wanted STOVL capability in the same aircraft(combining the needs of USAF and USN). When a 5th gen fighter jet was designed without all these complications, the result was the F22 and YF23...both with remarkable capabilities and though still challenging but without any project complications like that of F35.
3. J-20 (unknown, too new to make an analysis of)
So everything is not working out in the world of the Lockheed Martin invented "5th Gen"
It was China's first attempt and they had a lot of catching up to do. In any case it remains to be seen if there's any major issues with the J20 or if it was a success.
Pakistan or any third world country cannot afford to make such a giant gamble. Nor should it want to make a joke of itself with a "Qahar 313" or some other such rubbish.
What it needs is a low-risk, pragmatic and effective platform using the KISS principle.
Yes obviously Pakistan isn't as well off as the countries who currently have designed/produced 5th gen fighter jets and so a low risk project would be best. This is where China and possibly Turkey come in. China has already designed many of the technologies that go into a 5th gen fighter jet and Turkey has many experienced companies with a history of designing/producing avionics. This is where the low risk comes in...Pakistan wouldn't have to reinvent the wheel and can utilize a lot of the already established capabilities.
Using the basic layout of the JF-17 would mean pilots of the Azm fighter can train using JF-17s, lowering costs of operation, training, etc.
A bigger brother of the JF-17 would use essentially the same FBW system, tweaked. This would considerably reduce the time, effort and cost. We can see the LCA making the fatal mistake here.
The LCA was a blunder bcuz of two main reasons
1) At first India tried to develop every single aspect of it by itself and hence reinventing the wheel where it wasn't necessary. They could've instead taken a step by step approach like doing a JV with some country
2) Bcuz they tried to develop everything for it domestically, it took time...a relatively long time. Long enough that by that time, the previously agreed upon design/capabilities/avionics of the aircraft would have become obsolete by the time it would go to production. So the goal post was moved...now the new goal was to make it comparable to the modern aircraft currently on the market. This cat and mouse game happened for a while until recently where it was just forced down the throats of their air force.
A third possible reason could be the kickbacks IAF and some politicians/bureaucrats receive by purchasing foreign aircrafts, which may have caused intentional delays of LCA, picking foreign aircrafts instead. Though that's just speculation.
A stealthy, larger JF-17 would be an effective platform against India. Would cost less. Would cost less money and time to develop. Would be less risky. And would be very easy to maintain, operate and train with.
Just as Israel trains its F-15 pilots partly on simulators, partly on F-16s, the PAF would take it further and have such commonality that pilots could train easily using the JF-17, saving the Azm's airframe for an extended service life, low cost of operations and ease of pilot transition.
These are just my thoughts, opinions, wish, etc. I have no actual idea or inside source of what the PAF is doing.
A half baked and not truly 5th gen platform would honestly be just a waste of money. What's the use of an aircraft that's not fully stealthy? It will be detected. An example would be F15 Silent Eagle...it's LO from the frontal aspect and has some limited stealth from the sides and back...but in how many situations will it be facing enemy radar from the frontal aspect only? It just becomes an unnecessary cost for a useless partial stealth. That's why no Air Force on earth has inducted a half assed stealth fighter. They chose to spend more to get true stealth or stick with 4++ gen like Su35, Typhoon, Rafale, F16(newer blocks), F15(newer blocks...not silent eagle), etc. So Pak would then be better off with 4++ gen fighters altogether in terms of more bang for the buck.
What Pak can do instead(to save money) is currently stick with JF17 and other platforms it has. Skip over the current need of acquiring 4++ gen fighters for now and put that money towards a true 5th gen platform. Moreover Pak can keep the costs low by excluding certain things like TVC, or unnecessary things like the F35 has where the pilot can see through and around the aircraft(bcuz of cameras placed all around it) and by making it single engine(lower per unit cost/lower operating and maintenance cost). Azm can be the single engine multirole platform and Pak can acquire twin engine TFX/FC31/or J20 if possible for air superiority(with TVC) and longer strike range...together they can form the high/low combo with Azm being the backbone much like JF17 is now.