So the controller will be mounted in a box with the LCD in the middle and the encoders above and below. The distance for the I2c will be 10mm maximum. The controller is only to input variable signals into the uno Accelstepper code to vary the parameters of the actuator.
eg, turn encoder 1, sends I2c signal to nano 33, this then sends to the uno via serial connection and changes the value in the runspeed() code.
The LCD is for a visual display of how much speed, for instance a bar ranging from 0% - 100%
The controller is basically a input device for the UNO. it will be controlled by a 2m cable over serial connection to the uno.