It has taken a very long time and Pakistan has paid a heavy price to get out of the yolk of US influence. It will be a stupid mistake to go back to the same vulnerable position by investing in more F-16. We should buy as many spares as we possibly can to keep using the existing fleet for as long as viable.
Due to the US sanctions we went the Thunder route, but we designed a jet to replace tier two fighters, nothing wrong with that as that was a bigger chunk of ageing assets and in reality PAF did an excellent job in the shape of Thunder which is much more capable than the retiring assets.
Instead of starting the Azm project for 5th Gen fighter, PAF should have first started work on a medium weight category fighter to replace F-16's in the next 10 years, and gained more experience by increasing the share of work to 70 to 80 percent in full production. In the mean time the strike fighter requirement could have been met by inducting J-10, J-15, J-30, or a combination of these.
Only after producing the second jet, undertaking a 5+ or 6th gen project would have yielded better results and also would have made us more independent and self reliant in 2nd tier (f-16) class category in the 5th gen fighter age.
Since the 5th gen fighter will only form the spear head of the strike force, and main bulk would comprise of a medium weight fighter , I think it is still not too late to start work on a medium weight class fighter after completion of block 3. That new medium weight fighter does not have to be a brand new design, we can take J-10 as the starting point and modify/add what would be required in the next 10 years. A home grown jet would be cheaper, sanction proof, and will keep the momentum going in the nascent Pakistani aviation industry.