I am not sure if Gemini/Cosmo keyboard is any good (I trust Nokia N900/N950/Neo900/Fxtec more in this regard). Backlight is not bad, but I would wish for RGB backlight. Programmable.

External touchscreen is interesting, and has got to be capacitive to be protected against scratches, but I do hope that the internal huge touchscreen is resistive, for pressure-sensitive drawing. And external display should have lots of physical buttons around it, from accept/reject call, to volume wheel of speakers and microphone, to scroll arrows/navigation wheel, to half-press camera button.

External display better be OLED, for ease on eyes, and readability in the sun. Internal display could be black-and-white e-Ink, for books and emails and web pages?

Fingerprint sensor, LTE, Bluetooth, NFC are nice.

In short, where is the source code for the hardware, so that somebody could clone this device into something MTK-less and more Linux-friendly?

Thank you. Best wishes.
~~~~~~~~~~~~~~~~~
Per aspera ad astra...

[EDIT]
Fxtec is pretty similar: AMOLED screen, 6GB RAM with 128GB storage (EMMC, presumably), stereo-speakers on the side, 3.5mm (TLS) headphone jack, fingerprint reader that's not integrated into the power button, and of course the big wooping sliding keyboard.

But all the same, I can understand desire to hide the large screen from external scratches, by making it into a communicator form factor. But generally, I prefer slider. And, I miss resistive touchscreen. And RGB backlight.
[/EDIT]

[EDIT2]
Yes, external display is AMOLED, thanks for that at least. Internal display is Colour FHD+ (18:9), probably LCD I guess? 18:9 aka 2:1 sounds fairly nice - hip to be square. Space Grey Metal sounds very annoying - how difficult will it be to change it to something light, like shiny silver? Absence of talk/stand-by time is frustrating. FM radio is likely receiver-only, no transmitter. 3.5mm jack, is it going to be TRRS, or five-contacts? Any mention of volume buttons/wheel or 2-stage camera shutter key?

And will it run Maemo Leste? And will it be possible to put resistive touch screen on main display?
[/EDIT2]