I would do a subway tile that brings some color to your kitchen since it's kinda dark. Maybe blues & greens.

A modern glass tile in blue or green tones would add just the right amount of color. http://backsplashideas.com/glass-colors

The easy answer is to add color with the backsplash, but don't forget a backsplash is permanent. I suggest neutral with an interesting finish, maybe a crackle glaze. Add color with accessories or paint.

Red subway tile

keep it simple and not busy.

I also agree, always can add smashing color with curtains, small appliances and items on the counter top. Add some nice hardware on the cabinet doors and drawers. Subway tiles are nice, but a clean frosted glass tile can be stunning. Have fun with it, add something goofy too, just to make it yours alone.

Maybe try something like this type of backsplash design. Changing the colors to shades of gray and maybe add some white.

People tire of busy designs. I would think twice about subway tile.

Subway tiles are a little too trendy for my tastes. Only do it if you know you'll love it after the popularity passes!

if you could carry the granite all the way up from the counters to the cabinets - I think it is a great look and it is easy on the eye as you are looking at the same pattern throughout

Be careful about small tiles that technically "match" but would end up looking busy and dark. The ones you've picked aren't the best choice. Subway tiles are pretty classic.

You could go bold and add some color.

I would love to see a bronze/brass glass tile that would compliment the cabinets. Warm up the counter tops a little. The cabinets are dramatic and the counter tops are very plain. If you work with "camouflage" tiles (like the one's you have laying on your counter top) you are going to end up with a wall that looks like it was decorated by GI Joe. I know this is "the rage" right now...but it is my least favourite look for wall tile.

You have plenty of wall space...you could work with a single colour worked in a herring bone pattern like leelee shows above. The texture will help add depth to your finishes.