My main concern is that your proposed Block-2 upgrades and block-4 will stand against super sukhoi upgrade/ Mig-29 upgrade/latest Mirage-2000 and upcoming threats from the enemy, JF-17 is not jack of all trades or can't face these emerging threats from the enemy but PAF needs stop gap jets ASAP to replace our mirages and the best option will be either J-10C or Mig-35, than Project AZM will comes into play
A GaN AESA and EW plus advanced DRFM and networking equipped Thunder along with other upgrades with tech that would be available in the next 5 years will more than match all of the above.