While I started using copper wire because it was inexpensive and readily available, I have grown to appreciate it's earthy tone and rustic appearance. I recently began soldering and started with copper because I knew that there was going to be a large learning curve. The more I work with it the more I love using it and it is no longer a "learning and experimenting" wire, but a staple for me.
Copper is a naturally soft metal and therefore easy to texture. A little hammering and some oxidizing with liver of sulfur and you have a rich, rustic look.