Hi Joyce, your two walls look fantastic as they currently stand.
Your fridge, however, could use some editing.
Enjoy the nice, open, unfettered spacious clean feeling. :)

What is on the other side of the long wall? Could you steal a few inches for some narrow shelves?

It's odd. We sooo often strive for clean and uncluttered yet something, some opportunity is being missed here :-/ ...how about a barn door with hopefully access to a pantry, mudroom or laundry. I notice, like me, you have "stuff" stuck on your fridge so maybe a chalkboard or organizing system by POTTERY BARN would be useful instead of blank. Careful that whatever you put there doesn't catch on your shoulder as you pass by or come crashing down. Very basically, your paint is really bland which might be all you need to get started. Let's get some better color on those walls. At least if you used a richer colour the room wouldn't seem so unbalanced. All the weight of the room is on one side. It looks like you'd have plenty of room to fully open your appliance doors so...I keep going back to a reclaimed barn door which can conceal either a chalkboard, organizinizing system, shelves or a room for pantry, etc.. consider having directional lighting to those walls when you've made your changes.

I agree that the room could benefit from richer color on the walls- perhaps one of the darker greens or grays from the floor. I would place art or one of those rail systems on the back wall and the magnet board on the side wall. Paint it with chalkboard paint so that is has two uses- black if green walls, green if gray. Add track lighting.

In addition to the above, you might consider changing the layout of the current cabinets and an appliance or two - I'm thinking it's just the refrigerator. Moving the refrigerator more to the front section of the run might allow you to install corner cabinets at the location where the refrigerator now is which might then allow you to install additional cabinets along the back wall. If a standard corner base cabinet will not fit, then perhaps using standard 12" and/or 18" boxes could work. Doing this might mean that a couple of your existing boxes might need to be replaced with a few new boxes but it could still be a good trade off. If this works, then you could raise the outlet at the end wall to the standard height above the back splash. If you send me the dimensions of your current layout and the lengths of the two related walls, I would be glad to send you a layout. And since your cabinets look relatively new, you may be able to match the existing cabinets with good success, especially since it looks like the transition could start at the stove and hood and not necessarily at existing cabinets. If this modification is possible, then the other long wall would balance out more or less and would be a great place for a wash of light.

Don't put anything much else than a pretty paint colour.

I think this mossy green would look great on your walls.

Wall paper will fill that void.

how about a large pegboard system to hang often used utensils?

As an artist, I'd be tempted to tell you to put a large art panel there, but frankly, I think the large wall should be left alone. The space is too narrow and anything you put there will get in your way. I'd just paint it.

OR- What's behind it? Can you tear it down? That'll open your space up considerably.

http://www.etsy.com/shop/katshoa

Here is some wallpaper:

I wouldn't put anything on the large wall and suggest painting a color you like pulled from the floor.

Then coordinate with a nice piece of art you love on the back wall.

Paint, something warm earthy maybe khaki, something to complement the cherry cabinets and the slate tile.