I came up with it by going from a traditional keyboar, through a Planck, Atreus, a weird Alice-like ortholinear layout, and a 12-column version of Kamina, looking for my perfect layout. I’m pretty much happy with this one, except for the weird positions of ins, del and , but there is a compromise between that and the size, and I need it to be small, so that I don’t move my hands while typing.