That's great that you're thinking of sprucing up your curb appeal! I have a background in Interiors as well as in real estate so I have just the suggestions you could use. I'll give you a few here -- and you can call me for a more in-depth look at your own place to help me give you better suggestions.
You can put in a couple pots of hardy winter trees (like pines) along a long wall or either side of your entryway or garage.
Installing white christmas lights without a holiday flair but used as patio lights is a great way to add warmth.
A large wreath on your door -- a supersized one that juxtaposes the color of your front door would make the front entrance pop.
Of course, keep your driveway clean and attractive, including the area by the mailbox.
Let me know if you want some customized suggestions.