First of all,you can look at the number of systems in an airforce,by counting helos,transporters & training systems along with fighters(which I didn't do).Even if you did that,Pakistan's airforce would still be around 600 aircraft.Now going by fighter jets & recon & combat capable trainers,Pakistan's AF is still in the 400 to 450 region.
http://www.geocities.com/Baja/Dunes/1107/inven01.htm
http://www.globalsecurity.org/military/world/pakistan/air-force-equipment.htm
About Pakistan's F-16s,the number of aircraft in active service is rated to be at 28 or less given that several have been canibalised for spares & a few lost to attrition.The figure of 32 has been bandied about for close to a decade.
My link and both of your links say that the number is 32. Where do you get the number of 28 that are ready for active service?