not too busy- maybe a tad matchy. I would go with the gray glass subway tile.

They look like they are different depths & may be hard to keep clean. Nothing beats white subway tile say with light grey grout. It can be horizontally positioned, vertically positioned. It can be larger than standard size, it can be pillowed. It can be stacked end to end or standard running bond or you can be brave & go chevron or herringbone. You have endless choices with the good old standard (for good reason) subway tile.

And yes, it can be porcelain, clear glass, stainless steel............

Thanks guys! Thought so but we just love this back splash but kind of knew it didn't really work..