So fiannaly after all the component choosing it is the time for a schematic. 

In the past I used KiCad in several other designs. Ist is easy to use and why not use it as well on this design?

In the past I was often searching on my schematics for connections. Thats why I choosed this time to draw logical blocks.

In total we got 

- 36 RGB+White LEDs SK6812 or WS2812B (choose which is nicer for you)

- I²C Connector Interface for all kind of Air Quality Sensors

- a LoRa Communication Chip RFM95

- an ESP32 Wroom

- an EC11 Rotary Encoder with built in Switch

- 1 LED RGB for Illumination of the Rotary knob

- a low Dropout Voltage Regulator

- an programming interface

- one more interface for debugging or control even more Air Quality sensors e.g. Sensair S8 or  an PM2.5 Sensor.

- Space for an Light Sensor

Schematic V2 with some minor improvements: