I have been successful in create a bare minimum controller using atmega DIP board and .96 OLED to run opentx or ER9x.

This upgrade will cost you only arround 1200 and a loan of USAP to configure for first time.

you can use your existing CT6B case and receiver but with 9 channels and the features of expensive turnigy 9xr.

If you are using telemetry capable module then it can be configured also out of the box with addition of a hardware not over Rs. 100

http://www.rcindia.org/for-sale/atmega128-dip-bare-board/   board

http://www.rcindia.org/for-sale/96-inch-spi-oled-display/       display