Yes, the design of keyboard could be made easier by putting the pointing device (5-way or 9-way rocker, trackball or perhaps even the 4 arrow keys) on the LEFT end of the keyboard. Such a solution can also help making the keyboard symmetric. The center line between the left and right-thumb halves is between the T-G.B and Y-H-N key columns. This means that there can be, for example, 2 + 5 key columns on the left and 5 + 1 +1 key columns on the right. Here with 2 + 5 columns I mean the "2 keys wide space for the pointing device + modifier keys" + QWERT keys. "5 + 1 + 1" columns mean the YUIOP + Backspace key + 1-key wide margin (perhaps without any keys). Or, if the Backspace is not put on the right side of the P key, there can be a language-localized key, exactly in the same place as on full-size Qwertty keyboards: Å for Scandinavia, Ü for Germany, ´ for Spain+Latin America, etc. The right-thumb end of the keyboard always tends to be too crowderd (2 .. 4 localizable keys, Backspace key, Enter key, Ctrl key, 4 arrow keys,...). By moving the 4 arrow keys to the left-thumb end, there would be enough space for all the essential keys in the right-thumb end.

On the keyboard OH of Jolla there is one more reason to put the pointing device in the lower left-thumb corner. There may be a hole in the upper left-thumb corner. That hole matches with the camera lens, allowing you to photograph thru the hole without sliding out the keyboard. Because the camera in in the middle of the top (left) end of Jolla phone, the hole will become visible in the left-thumb corner of the keyboard when you slide out the keyboard. Because the hole would be close to the Q key, on the left-thumb side of the Q-A-Z key columns is left an empty area, the middle and lower part of which can be used for the pointing device or arrow keys.

I'm right-handed, but I do not mind using the pointing device with my left thumb. Also for phone use I prefer keeping the phone in my left hand: then my better (right) is free to do other tasks while calling: to open a door lock with a key, for example.