Actually i have and i mentioned down precisely in the last part of my post that i did write about J-11 and what PAF can gain out of it somehow my comp hanged up and my post was lost and i did not felt like writing it down again.
As for the technical aspects, its actually difficult reason being because due to the relationship between the west and China, the upgradition of J-11 with western avionics will be close to impossible.Whatever systems we will get will be Chinese(Radar,EW suite etc) Also because of the copyright issue, it would be difficult to obtain from China, third the demands for the PLAAF have not been met yet alone PAF seems far fetched.
J-11 is a large jet and has added advantages because of its payload, range and because of its larger nose, a bigger more powerful radar could be opted and not to forget twin engines are always safe in case of a engine failure the jet could still be brought safely on the remaining one engine which will not be the case in single engine jets however that comes with a price and maintaining twin engines is always costly.