The idea behind having an indepth look at payment gateways is to ascertain how mcommerce works from an end to end perspective. As you rightly surmise, it can take upto 2-3 years for the various regulatory reasons , coupled with the fact that these are macro-economic partnerships that have largely been the domain of big players so for a rank outsider it is almost impossible to penetrate.You core offering might not be a payment gateway implementation , or even a mobile wallet but in order to participate in mobile commerce industry the first thing is an indepth understanding of the market forces and the players involved, which should enable you to present your skills as a e-commerce m-commerce solution provider, even if it means partnering with existing players . Hence the reason i was suggesting you to meet up with those payment gateway startups and begin networking with them. Sooner or later you are bound to hit upon an opportunity in the space, which you and your new found contacts can exploit.
The whole idea of entering a market like mobile commerce in India is to be a differentiator, and add value to the industry. The kind of security and features that ApplePay and Samsung Pay will offer indian customers is going to be almost impossible to beat, EXCEPT if you can come up with a specific feature with your knowledge of the indigenous aspects of trade and commerce in India.
Can you give us some insight into your background in this space ?