+1 for the cellular expansion card for me
Other ideas that could interesting IMO:
- A PCIe / mSATA slot as suggested above. Even if it sticks out a bit if needed?
- Maybe a bit too specific but one thing that sounds possible with this and I would like is a simple USB-A port going slightly inside the laptop, so we could leave all kind of small dongles like logitech unifying on without them raising out of the laptop, or even an “internal” USB port with a closable plastic lid so the receiver is hidden inside and the laptop appears flat and port-less.
- And finally, a video INPUT card (HDMI and/or USB-C) where we could plug some video emitting device like a digital camera, a console, etc… for streaming or just to use the screen as a display, like this kind of thing.
Of course these may be too low volume to implement but if the system is open enough maybe third-party could do them?