1) By your logic if India had 100-150 kt weapons in the 80s-90s then why did India only test a 60Kt in Pokhran 2? Doesn't make any sense strategically. I mean they should have tested a megaton in that case.
WHY..? It's better to have 2-3 100 kt ones than a single megaton. And yes you don't need to test to 300 kt but can simulate results.
2) India does not. Please point me to a source saying India has a MIRV equipped missile. It is a big deal. You can do 10x the damage with an MIRV equipped missile than a regular missile.
A5 is MIRV equipped. So will k4
3)
4) My friend, I am talking about second strike, assuming the first strike is counterforce and wipes out all of India's land based missiles.
For china even land based are enough. But underwater canisters like pontoons are always a fall back. No one will tell you how many.
5) All I am trying to say is, that there is a seed of recreation which is hard to destroy.
Not for human beings may be a new specie will evolve and take over that can survive in radioactive waste land