1To me, a house with a plain door seems like an outfit without jewelry. It doesn't offend, but a great door can give the whole house personality. It's an opportunity to add color, sparkle, even whimsy.
By far the easiest way to give your door distinction is by painting it. Ideally something really great like the one above. For a more traditional setting some good colors are pear green, canary yellow or sky blue. If you're willing to be daring you could try lime, orange, or even pink.
Good hardware will add polish to your door. Something with sparkle will take years off the facade of your home. On a practical note, the knocker and the knob should be in the same finish.
And there's no need to stop there - you can paint the doors inside your home too! It's a great way to add color to a room when you don't want to go all out and paint the walls. It also gives you the freedom to use stronger paint colors since you're doing just a small patch of color.
Photographs: 1. Kelly Wearstler's Modern Glamour 2. Uppercase via Apartmenttherapy 3. via Foxgloves, Fabric & Folly 4. Domino Magazine 5. Kelly Wearstler's Modern Glamour 6. Domino Magazine