I believe the air chief has stated that these f-16s would be improved further. 3000 hours life means they aren't exactly falling apart. F-16 is F-16. You take care of it, it will last. You screw the maintenance and even a new F-16 will have trouble. What i mean to say is, these are certainly better than the antique Mirage III/V we have. All that is needed is upgrade to better avionics, the full MLU and perhaps FALCON STAR. As a whole i am not in favor of more offensive US equipment, but a system that has been used by Pakistan for decades is always a bonus. Spare parts should be plenty, since Turkey might be retiring some units soon and/or have a large stockpile of spare parts.
Now, i agree with your last sentence. In the current form, these F-16s are not very healthy. Since PAF refused to take the USN units (stating that they were driven too hard) i am sure they would have thought the same with these RJAF units. They would have seen that these units have life and can be upgraded.
I don't know the exact details, but i believe these will be upgraded. When, I don't know.