PAF need one aircraft that can take the place of F-16 right now. As a multi role platform JF-17 has done well, even block3 will be a fighter that is unprecedentally success. What is sighnigicant for PAF is too get a fighter which has patent superiority to IAF 4th generation fighters( Mirage 2000, Tejas, Mig29K) and competent to defeat 4++(Su-30MKI Rafale), More importantly deters the Su-50 and AWACS.
When facing those rivals. Amount takes a fraction, 100 J10s would be inferior to 20 J-31s I think, because J-10 is not enough to validly imped or destroy them and self casualty would be unacceptable.
Asymmetric superiority is the only way to fight against them. Eliminate more enemies and diminish self loss. Like 1 soldier with pistol fight with 1 with another pistol they may kill others equally but if 1 with Machinegun and fight with 10 with pistols the 1side maybe loses 0.
I think at least J11D as you said. J10 maybe has the cross of role with JF17 block3.
J31 is ideal. I hope China and Pakistan could manufacture it together.