@Minator

None-replaceable internal storage is a no go for me.

Ideally a Snapdragon CPU with M.2 SSD, USB 3.1 A and C ports, ExpressCard or Thunderbolt ports, user upgradeable RAM and a 4K screen. And none of that ChromeOS rubbish unless I can put it in developer mode and install a proper OS. :)

Or as i said, an ATX mobo with ARM CPU and a few PCIe slots.