Hi! I love the photoshopping! You got the point across. And it looks like you'll have a lovely kitchen.

Am I allowed to vote neither? I can see your dilemma. You'll have either a green stripe beside the window, or a lonely strip of tile. I would vote for the tile if tile to the ceiling if it could be repeated somewhere else in the kitchen for reference. (Or if it could run over the window as well.) I would vote for the paint if you were changing color to something nearer the cabinet color.

If I were you in this situation, I'd get a veneer strip painted to match your cabinets. It appears your cabinets match your trim color on the window. Fill in the gap between the cabinet and the window up to the top of the window trim. You can top it will a small piece of horizontal trim and keep the green running over to the cabinets. You probably won't even notice the strip of wall that way.

Hope that helps!

Can you tile to the ceiling AND over the window? It's hard to see the whole space as you only show one side.