Non-radio communication between ships is very much in use, a few month ago I had a request for information answered by the German Navy. They still use optic telegraphy (like most other navies), including the capability to send one signal to several ships at the same time. This wikipedia image illustrates one solution:
From various wars and studies, it's well known that optic telegraphy can be used in the 100-50km range - quite enough for a group of naval ships. A major advantage of optic telegraphy has always been the very limited ability to detect anything outside a close proximity to the target area where the signal is sent to.
As for modern communications, optic telegraphy still enables an undetectable communication for coordinated measures with less undetectable tools.
Russia does use Indian bribery to their advantage, but India also profits from their longterm relationship with Russia and can always switch alignment, with the US and China being no less capable of paying bribes and organizing hot chicks.
Concerning Russian carriers, they have a clear philosophy and tradition of missile ships with ever increasing helicopter component and finally with the capability for fixed wing fighters. The US tradition is one of fixed wing fighter carriers with later additions of helicopters and missiles. Both, the Russian and the US designs, are called aircraft carriers, it's apples and oranges. The Russian designs are not meant for the same kind of operations as the US design and to some degree they are better compared to US LHA (that still lack all the missiles). Aircraft carrying cruiser was not a bad description.
For Russia, the business with India is crucial in order to maintain shipwright capability and all the problems rather highlight how important it was for India to step in and save Russia's skilled labour. I'm sure, China will master a much quicker assembly line than her Eurasian would-be competitors, but I'm not sure, India's choice to support the Russian know-how base was a bad decision from a longterm point of view. It's this Russian base that will be crucial to all Indian carrier developments. Choosing the UK or France instead, would have made them much more US "bed-fellows" (resented because many Indians consider themselves a great power with regional ambitions), a more grabbing alignment than the less powerful Russia. Going down a road of almost all indigenous development could certainly never finance a competence level on par with the Russian alignment, because India is not the economic giant that China is.
The Mistral-class purchase from France adds a lot new input to Russia, not only in amphibious warfare, because of the strong helicopter carrier core of Russian naval aviation. The current Russian work for India is possibly the last pre-Mistral-class Russian carrier that will markedly differ from the new designs after the French influence impact. What trajectory will Russia, China and India then take, after having started from the same Soviet templates?
