I'm not a board designer, so this is probably very naive, but it works for building ESPHome-based sensors and other small IoT projects.
All the GPIOs on the "inner" rows are routed to the terminals, so there is no need to solder all of the pins on the MiniKit all the time. The (optional) NPN transistor (and 10k resistor) can be used to sink an external LED that mirrors the on-board LED but that requires that GPIO2 be soldered through as it sits on one of the "outer" rows.
Get bare boards directly from OSHPark: https://oshpark.com/shared_projects/CoKjk6w7
- ESP-32 MiniKit: https://www.aliexpress.com/item/2251832629758482.html
- Power Supply: https://www.aliexpress.com/item/2251832424359134.html
- MiniKit Shields: https://www.aliexpress.com/item/2251832856833499.html
- Screw Terminals: https://www.aliexpress.com/item/3256802913222907.html
- IO20 labels on the underside should be "IO23".
- All 6 pins in a row in the prototyping array are connected together. I should have done 3+3 so an IC could be used.
- Make the 5V and A/C traces wider
- Add protection to the power supply (https://forum.mysensors.org/topic/1607/safe-in-wall-ac-to-dc-transformers)