So I think we need to revisit how the training process works because i think many of us, including myself may have some misconceptions.
First cadets are put through basic flight trainers such as Super Mushak. These train would be pilots on the basics of flight and how to control a piston engine. Now from here you move them to basic jet or in the case of some forces advaned turboprop trainers (T-37/BAC Provost/Saab 105 for basic jet or turboprops like Embraer Super Tucano/Beechcraft T-6 Texan II/ TAI Hurkus/Pilatus PC-21 which have started to replacebasic jet trainers in many nations d/t similar performance and cheaper costs). From basic trainers you would move the cadet to intermediate or advanced trainers like K-8, L-15, JL-9/FTC-2000, T-38 talon, Alpha Jet, BAE Hawk, L-159,and M346. Then they move to OCU where they operate two seater variants of their fighter jets (F-16B/D, JJ-7, JF-17B, ect). With that said how does K-8 fit this role.
The K-8 program worked for Pakistan because nearly 530 were built and sold. It was actually a farely successful product, so PAC gsined a littke experience learning from the chinese, amd generated some revenue as a 25% shareholder. But the aircraft has a slight identity problem. It is marketed as an intermediate jet trainer and an advanced jet trainer. In the modern PAF, it is likely more of an intermediate trainer. With that said i think what role it fills has more to do with the makeup of the airforce that is using it rather than its own capabilities. While PAF was mostly using F-7 and MIRAGE III/V, it could function as an advanced trainer prior to pilots being deployed to their OCU. While ut can mimic flight characteristics of more modern jets, it does have the advanced systems and avionics necessary to train pilots for a more advanced fighter like F-16, JF-17, J-10, ect. That's why the chinese developed FTC-2000 and L-15. For PAF much of their advanced training was done in the Mirage and F-7 OCUs and their superior pilots eventually made their way to F-16 OCUs or the JF-17 via flight simulator training. But as PAF gradually weans itself from Mirage and F-7, the gap from K-8 to F-16/JF-17 will simply be too great to cover in the OCUs,hence the need for an advanced trainer. My suspicion is the PAF will likely start phasing out its T-37s and that void will be filled either by a turboprop like Hurkus or more likely by K-8 (there a are 60 T-37 a d 60 K-8 in service). The main question is why PAF hasnt updated the avionics suite of K-8 to demand more of an advanced trainer quality, but that is a question that more senior members may be able to answer.
As far as the options for advanced trainer, the choicer are BAE hawk, L-159, and M346. While the L-159 makes the most sense as an isolated purchase i. That it is the least expensive, the M346 has some of the best flight characteristics (given that it is basically the same aircraft as the Yak-130 which is one of the premier advanced trainers) and it is ITAR free. Additionally, it has the added benefits of being a leonardo product, a company and country (Italy) that Pakistan has good defense relations with and it is the largest operator or leonardo radars outside Italy and Britain (typhoon) in the world and operates the AW139 helicopters (AW is part of leonardo). The M346 could be leveraged into a larger defense deal with the addition of more AW-139 Maybe even with ToT, CAMM-ER for the PN MILGEM/Jinnah program and possibly even Grifo-E for the JF-17 Block3 IF EUROPEAN WEAPONS and sensors can also be procured (mainly METEOR, Iris-T and A2G munitions as well as Skyward-g IRST and BriteCloud DRFM, SEER RWR, and BriteEye Integrated Defensive Aids Suit which marries SEER amd Britecloud and gives enhanced RF awareness to the pilot). This could form the basis of a highly capable European sourced variant of block 3 for export and high end ew mission capable JF-17 for PAF. Of course even without the Grifo im sure many of the other systems could be integrated into JF-17 as well as part of a package for M346 and CAMM-ER.