I would personally suggest we leave real policy decisions to the ones that actually know what the **** they are talking about. Unlike the OP. Regardless the strategic depth strategy has value even now. Pakistan needs to maintain some area where it can launch a counter attack should India feel it can attack the country.
we are not living in the 16th century, or best defence is political.If india does launch an attack and capture a sizable portion of punjab then the game is up !
pakistan cannot exist without punjab whether we like it or not