Hm, you convinced me to go straight so USB 3 
.
Spent like half of today with playing around and optimising the schematics. The routing of the USB-lines is complete (not finally but to get an idea of the space needed. Power is at like 0% (the capacitors scattered on the top corner are part of that and have to be placed (and there have to be more of them). Also the programming lines of the hub-IC has to be done entirely (and I have to figure out what exactly to do before ).
I’m using this hub-IC: USB5744 | Microchip Technology
It’s the smallest one I could find. Also I’m implementing the USB-C ports as four seperate ports (which can be done but is probably not best practice).
The major parts alone are currently around 30€, plus the PCB, plus manufacturing (which I’m not sure how expensive that could become), so I’m not sure if it finally is economically worth it for a second USB-port (but I like the project).
