Pakistan has offered no deal so far to US for them to hand over 40 F-16, block 70 or advanced Patriot 3 missile for free to Pakistan. These will cost upward of $15 to $20 billion.
The deal Pakistan can offer to get that kind of aid, is to kill Taliban as an organization both in Afghanistan as well as its support structure in Pakistan to end conflict and finally end terrorism as a state policy within Pakistani borders itself.
So far Pakistan has offered a very limited support to force Taliban to the negotiating table. For which they got $125 million in prize money, very little in hardware upgrade but 60 US personnel to upgrade existing F16s. These have not been upgraded since 2008/9. There is a definite problem in current software - hardware of F-16s with Pakistan. None of the five AAMRAMs fired by the F16s at Indian Sukhois, hit home, these were easily sent in the wrong direction. That means upgrades are needed to the current f-16 softwares and radars, hence Lockheed Martin personnel are coming to fix that problem immediately. Anything more would require more from Pakistan.
For Pakistan to end all support to Taliban and end conflict in Afghanistan require first change of public mood. That is the hardest job to do. A lot people with free wheeling Madrassas have to close. A huge number of bearded Mullahs will have to end in jail etc. That much Pakistan will not do, hence free F-16, block 70 and PAC -3 are not arriving anytime sooner.