I like the look of the tile around the window, but I think with this particular tile that has a lot going on it might make sense to do it under the cabinets and live with it a little bit and see if you feel it looks naked and "needs" something above the window. I fear if you do it all at once - although I know that is more convenient - and feel it's too much it will be harder to go back.

I totally agree with Sam. I love the look of tiling to the ceiling but when I think about it I only have responded to it when it was a white subway tiling (or something very plain). Your tile has so much character, that I would take a breath and see first. Plus since your cabinets are (gorgeous and) white, that tiling around your window may make it seem very imposing.