For those of you who want an extremely simple build, I've reduced it to just 5 parts: one 1-megaohm resistor (0805 SMD) one Arduino Pro Mini one Ra-01 LoRa module Male header pins Battery clips See photos.

@sundberg84 - ok thanks, it makes sense ;). I was asking because I connected your Dimmable Led Strip daughterboard via MysX to this Easy PCB. Dimmer daughterboard is providing 5V on PIN3 (when LM2940CT voltage regulator is used on it). This would bring 5V to output of voltage regulator on Easy PCB so I disconnected PIN3 connection between dimmer daughterboard and Easy PCB. I connected PIN3 from dimmer board by wire to >3.3V power input of Easy PCB instead. Other option I'm thinking of would be not using voltage regulator on dimmer daughterboard at all but use its 12V raw voltage provided by dimmer board via MysX PIN1 (+ raw jumper on Easy PSB) and use voltage regulator (LE33) on Easy PCB only.