I doubt it will be viable.. Even 1 instance of NOW is very heavy... what is required is a new platform... something like odin or pib. They are very light on resources. And I have run MANY accounts even on a dial up line for many years, whereas for one single connection of NOW. 512 kbps to 1 mbps is being suggested.
Solution will come ONLY when zerodha guys develop something of their own. And when they do, its curtains for the other brokers!!!!!!