Is producing new design warheads like designing cars that you will roll out one every 3 months?
And what did I tell you about India already having enough fissile material to produce at least 2000 warheads. Yes 2000 and this from the fissile stock dated 2005. Add 7 years and also add the fact that india added 6000 super critical centrifuges for enriched uranium. India may have about 10,000 such centrifuges.
Why do you think India is ready to sign the fissile material cut off treaty while Pak is not? India is sitting pretty on very good quantities of fissile material which can be converted to warheads.
Why do you think India is happy with the nuke deal? It can free up fissile material for military applications while using imported ones for civilian.
Pakistan cannot win a nuclear arms race with India. Understand this fact clearly. India keeps a low number of warheads as it thinks it's good enough deterrent. India can up the ante any time and Pakistan will not be able to match up.