I think simulation testing is fine but we will need to validate the new designs.
High level chip development follows below procedure:
1. Design HW
2. Develop embedded SW for HW
3. Test on hardware emulation
But on silicon, we have to bring-up again to validate the chip & normally its pretty much hard work
. We may have a validated design on simulation.. but that's not verified till we test the yield.
I m pretty sure this is even more complex than I can think. That is the reason countries perform so many tests to perfect designs. You may be right that now is not right time to perform test.
Why do we need to do more live tests
It will be a suicidal move. Will never happen.
As far as I am concerned what will happen is simulation tests only.
Either at indian facilities with indian data or possibly somewhere else with own data or possibly somebody else's data.
India I believe is already conducting sub critical tests inorder to refine existing designs and scale up the present design in terms of yield.
Scalable computing is enough live test is old Phenomenon needed In cold war times
Today in 2018 I think Indian has enough data of it's Thermonuclear warheads and fission warheads from the pokhran tests
India definitely upgraded the design basedon current requirement
Of what we know India has has successful warhead design for fission And fusion based weapon yeilds btw 250-300KT I think it enough based on current threat perception
All we need is upgraded delivery system and MIRV demostration