[noggin]

I almost bought a Chinese Android box when I first started looking into Kodi, cheap way to try it, but I quickly got away from that idea.  General purpose SBC seems the best way to go with Kodi on Linux.

What other decent SBC boxes are available apart from Odroid C2/N2 and (to a lesser extent) RPi?      

Haven't been on the forum much so sorry for the late reply. 

There's several AMLogic SBCs supported by CoreELEC.  Of course the Odroid-N2 was the first of the S922X boards, but they're currently working on support for the Khadas VIM3. There's also the older S905X boards like the Odroid-C2, Libre Computer Le Potato, and Khadas VIM2.

Beware - I'm pretty certain the ODroid C2 is an S905 not an S905X box - so has zero support for HDR.