One of the most effective ways to upgrade any kitchen is to change the hardware. What is hardware? Hinges, knobs, locks, etc. The hardest part might be choosing the style and finish, as there are a dizzying number of choices. It's a good idea to buy one knob, install it, and live with it for a while. If you still love it after a week, chances are you are good to go. To make it easy on yourself, you may want to choose replacement knobs or pulls that have the same amount of hole(s) as what you are replacing. This will avoid having to drill additional holes or having to fill holes and touch them up with paint. If you do have to fill holes, use wood puddy, let dry, sand, prime, and paint.
For my kitchen, I decided to go a bit off the beaten path with the pantry. I built it to look like an old wooden icebox, so I thought it appropriate to buy actual refrigerator hardware. After a quick search online, I found a commercial supplier that had just what I needed.
For the rest of the hardware, I again used some slightly non-traditional choices, including a latch and unique bin pulls.
So the next time you open that kitchen cabinet or drawer, think - upgrade!