Looks more like PAF is getting J-10 jets solely for handling PN activities while keeping F-16's & JF-17's for PAF activities. Do not be fooled by US gov & Pak gov current relations. PAF and USAF go a long way back and relations are as good as they get and are not going to change anytime soon; hopefully.
A senior member(i believe it was Oscar) whom recently explained correctly how the US knows how to balance relations between IND and PAK and make sure that PAK does not get out of their grip. So, I would not bet against new F-16's or even upgrades for existing ones, just yet, since this purchase of J-10's helps in building a case for the US to send some goodies our way to maintain some sort of leverage. But, lets be sure this time to decide the amount of leverage ourselves.
Hopefully the PAF gets what they have planned for since they have hit the nail on the head so far and therfore never let us down; Mashaa Allah. So lets pray that that this time they too also make us proud and divide assets accordingly; Inshaa Allah.
Also, i believe they are working towards: data data data data..recieving, analysing, planning and execution(think of it as IOT for an airforce) all within seconds for different fields/areas(water and land) using a combination of Eastern and Western technolgies with a topping of indigenous ingenuity - I am praying that is the case - since the present and future leader of aerial warfare will be the one who has mastered the art of building, maintaining and controlling a data centric environment in the air domain e.g. F-35(a single tiny piece of the puzzle).
Cheers