What nonsense are you posting!!!
Long range rockets have flight path very different from small/medium calibre rockets, they come down at near vertical direction which no mountain can stop it. May be your indian rockets behave differently. And how are you going to counter the mobile rocket launchers that is constantly on the move? Using your satellite or counter battery radar? They will be moved within 3 minutes after firing and your target location becomes outdated immediately.
Nearest Chinese airport is more than 200 km away, other than using missiles, you have no way of hitting them.
And what is it nonsense that you wrote "MLRS are basically useful in planes that too when they have guided rockets as trajectory should not be hampered by mountain ranges..."