As to the relationship between India and Pakistan, I would say that it is practically impossible to have a security architecture in this region. Looking at the relationship between Afghanistan and Pakistan alone, which goes back to the creation of Afghanistan and Pakistan, it is a deleterious relationship. Even with regard to the border, there is no agreement because of the Durand line. Further, Afghanistan was the only country that did not recognize Pakistan when it was founded in 1947. Since then, there have been three successive wars between India and Pakistan.
Then there is the very concept of collective security. I still disagree with those who denounce NATO. While it is true that NATO has some problems, it is literally the only stable security architecture in the world that provides some balance. NATO's problem is that, after focusing so much on defending its own perimeter, it is now playing a role outside its perimeter, which has led to the catastrophes in Libya and even Afghanistan and Iraq, although NATO did not take action in Iraq.
The ASEAN architecture, on the other hand, has a completely different dimension. There will be no security architecture. In any case, China by far prefers bilateral agreements over restrictive multilateral agreements, which limit its range of action.
The NATO model is therefore unique and it will certainly not impact the Asia Pacific, where it will in any event be managed bilaterally by China and its partners.