Thanks for your answer.Hi,
It is a complimentary high end 4.5 gen addition to the PAF.
PAF has stayed away from a twin tail twin engine aircraft---due to operational costs---& maintenance heavy issues---.
It really does need a heavy strike aircraft which can carry at least 2 anti ship missiles 1000 Kg weight class each.
I presume however that a possible J-16 strike a/c it is more of a financial issue, then a maintenance/qualification issue - even though the "costs" are indeed an undeniable factor.
It could very well be that in 5-10 years (certainly depending on the GDP) the next step of the PAF might be directed towards a J-20 instead of a 4.5 generation J-16 or in case of following a single engine doctrine it could be a J-31 just as well.
Till then keep complementing/phasing out F-16's with the J-10D/E/F