In 1965, 1st Armored Div had minimal infantry support which is why tanks were shot up easily by Indian RRs. If Infantry had been deployed effectively, they would have flushed out the ambushing Indian forces. Tanks cannot advance without infantry, tanks cannot operate on their own.
ATGM is a defensive weapon. It can be used offensively, yes, but the main offensive weapon of an Army is Tank. There has to be sizeable offensive force in every region of operation. "Counter-attack" is a term used in military which is used to offset advantage gained by the enemy. Did you read about Rommel's campaign in Africa ? He never consolidated his position by building defenses, he kept advances with whatever force he had. It's a gamble as he retreated twice along the route that he won, but a middle approach can be sought. He kept pressurizing his enemy but neither he nor his enemy could get a foot hold of territory for long till Montgomery came along. Rommel's example is extreme, however counter attack is important. Infantry has to be supported with tanks against enemy infantry and if possible by strike aircrafts. So if Indian Army attacks and captures a Pakistani village or town, Pakistan should have sufficient armor along with majority infantry to counter-attack not just captured area, but also attack Indian reinforcements pouring in to consolidate that area, attack Indian supply lines to cut off enemy's link from its rear and also to defend against another attack when the reserve battalions are thrown in by Indian Commander which had been held back initially. For all this, Pakistan needs Tanks. Infantry cannot handle all these Military build ups by Indian Army. Most importantly, after Indian Army is dislodged from pakistani soil, then tanks are needed to attack Indian forces in Indian territory. All this cannot be done with ATGMs alone.
Pakistan uses its Brigade sized forces or Ad-hoc brigade sized forces effectively. This was seen in deployment of Changez Force in 1971. If you read 1971 war threads, you will see that atleast one brigade of every Division had performed much better than the whole division on its own. US Military has moved to Brigade Combat Teams (Stryker Bdes). India has moves to IBGs which are larger than Bde but smaller than Div. Pakistan itself is expected to use mixed Brigade sized forces comprising of armor, infantry, artillery, AD, Gunships to stop or delay a much larger Indian force.
Through Pakistan Military's deployment, now there are 4 armor/mechanized divisions capable of penetrating into India at four various places instead of a single area like you want. Concentrating all the armored force towards a single target will attract IAF, missiles, ATGMs and lots of Indian infantry in that area. Pakistan will lose initiative elsewhere. India will use minimal armor forces to counter this Pakistan Armored Corps size thrust and then India will create its own Corps sized Armored forces using that force to enter Pakistan hundreds of miles away. Pakistan won't have sufficient tanks to stop that Indian armored attack and then counter attack.
Plan-B is Second Div strength force of FC which is now operational.