As a note on transmitters, on all of my non-weaponed bots I use a 3 channel transmitter (old spektrum DX3) with an onboard mixer, and it makes the bots very easy to control. If I chose to, the third channel could be used for on/off or simple(two position) servo control.
For stuff like the DX6, I prefer single stick driving, but it really is down to personal preference.