A while back I started a project known as stormduino. Stormduino is essentially an arduino uno R3 clone made in Kicad with some slightly different components. For those of you who don’t know what KiCad is, it’s a pretty powerful open source electronics design tool that you can check out here: https://kicad-pcb.org/
After a few revisions of the PCB, I managed to get a working prototype. The project is open source so you can pretty much do whatever you want with it.
Here’s the github repo if you want to check it out: https://github.com/Chromico/stormduino