A few simple (and cheap!) improvements we've made recently were the light fixtures. I forgot to take pictures of the "befores" but trust that these lights are an improvement. They're probably not what we would have installed if we were staying in the house, but they are definitely a more modern look than what was there before and a cheap upgrade to make.
Brian installed this light in both the entryway and our hallway (these lights are a bargain on sale at Home Depot, 2 for $14!)
And this light is right outside of our pantry in the kitchen ($9 at Home Depot):