Hey, thanks for that. I only need a broker whose trading platform won't go out of service at important points. I don't need any of the data or charts stuff as of now.
If you do not need any Chart stuff, then I would suggest you to place your orders using NEST (search YouTube). NEST is very light, simple, stable and reliable for order execution purpose only. You can choose any other discount broker, they all provide NEST.
Try Fyers once, call them up and ask for a demo id. Fyers' platform and OMS is safe until their servers gets overcrowded without a ramp-up.
You can also try out TradeSmartOnline, their brokerage is the cheapest but reliability is a concern.
I don't know whether its a rumor or true, Upstox is backed by Tata. So, with Upstox you can safely keep your money and their accounting or back-office part is elaborate, simple and lovely. But Upstox's web-based platform is deteriorating day by day.