Paint isn't the only way to add color. Consider adding a bright red (or yellow or green) pendant light. Or, spray-paint an outdated fixture over your breakfast table in a surprising hue. This is also a great way to visually break up a kitchen with a lot of dark cabinets.
Displaying artwork is often overlooked in the kitchen, but it's a perfect way to add color and personality to this busy space. Consider vintage-inspired posters, food photography or, for an extra-colorful touch, frame some of your kids' masterpieces. A pretty tea towel in a frame is also fun for a kitchen wall.
A colorful backsplash can be a real showstopper in an overall neutral kitchen. If you're looking for an easy DIY project, there are a lot of peel-and-stick options now available. Or, experiment with something less permanent like a removable wallpaper.
Sometimes, refreshing your kitchen can be as easy as bringing in a few colorful accessories. Metal barstools come in all kinds of playful colors for an instant boost, or consider adding a fabric window treatment for some pattern play. Looking for instant gratification? Sometimes, just adding some bright, new dish towels or fresh flowers will do the trick.