Worth noting that if you want to use an analogue device (such as a joystick) for something it should go in the first column. As an example, I have an analogue mini-stick on my throttle that I use for Up / Down / Forward / Reverse thrusters, so assign those in the first column, and could also use the four arrow keys on my keyboard to control those thrusters too, in which case I could assign them in the second column.
The difference is that the mini-stick will allow 'bleed', so if I push it up, but also slightly right my ship will thrust up right, not straight up, but if I use the arrow keys (digital) there can be no 'bleed'.