France will never let HAL install Kaveri and Uttam on the Rafale. They tend to be very possessive about their 'exported military equipment'. Also; they are very welcoming, and expensive so 'PAF ke haat aya aur muh na laga Rafale' can be said about the current PAF state of affairs.
I think another batch or two is not needed, I personally recommend another aircraft for the IAF and Indian Naval aviation fleet requirement. Most important, these guys are going to be so worried about the aircraft, they wont be trained to a level of a self designed fighter will get them to be.
Upgrade the HF-24. Full control and no stress can make wonders for now the pilots are living, instead of 'graving' their career. I know this sounds very far, upgrade a fighter that was retired in the 90s, whats the point it will be made into a platform which is totally composite, super maneuverable and stealth inclined but the fact of the problem can be killed by just doing that.
With two Kaveri delivering 162 KN wet total on a already proven, now composite airframe will get it to super cruise. Imagine a F - 35 cockpit setup for it, how uplifting it will be for the country and the pilots and aircrew that were assigned to the original.
Its a big high to possess such a great upgraded historic enemy killer just after IAF sent Mirages over the border. Wars won can make one dream of its return, stealth and beyond.