The costs would be exorbitant for the Indian economy and military. Any large-scale exchange of projectiles and CMs between both countries laden with conventional warheads would ultimately truncate Pakistani offensive capabilities but not before Indian military/economic infrastructure is sufficiently weakened. Remember that India today does not face threat from a single border. The longer the Chinese allow India to gain strength and integrate into the QUAD framework, the severer the nature of the threat will become for China. In the event Indian gross national power is significantly affected, China should make its move if it is a rational actor. I think a similar line of reasoning would give the Indian state a cause for moderation in its posture towards Pakistan. It seems content, for now, to bleed Pakistan through proxy conflict with Pakistan not repaying the favor in kind. What we need to do is become as thorny an adversary as we can. So much so that any conflict would result in unacceptable losses to the enemy. To establish such capabilities that deter aggression, Pakistan needs large inventories of CMs, and BMs. Technological advancements, not just numbers of these weapon systems would be a necessity as well with a growingly complex AD environment.
That is why Pakistan needs an equally problematic (for its foe) solution to this problem. When it is a matter of survival, nations go all out (North Korea). It is perturbing that even after years, we have not entered into long-ranged supersonic CM age. The turnkey Chinese solutions we have acquired are confined to short ranges as dictated by global arms control norms.
I doubt if these systems have the ability to obliterate underground storage facilities. Such devastating weapons as Brahmos would not only be stored in on-ground structures. There must be subterranean infrastructure to ensure their survivability in the event of a counter on storage sites holding them.