Just found this design and I think it's totally awesome. The new super-small switch PG1316M is used to fit 3 rows into such a constrained space.

Wonder if you could even get away with 4 rows of this, especially to somewhat compensate for the lack of thumb keys? I'd personally be interested to try 4 rows even for a more conventional tabletop keyboard.

EDIT: I have accidentally erased the main URL when I tried to upload a picture. Apologies. (Didn't know Lemmy works this way). Here's the main URL for this thing: https://www.reddit.com/r/ErgoMobileComputers/comments/1npnj85/btyp_a_mini_pg1316m_switch_keyboard_for_use_on_a/