Summary: In most situations it is advisable to create your own customized header image. Sure you could use the standard WordPress Site Title and Description but remember, your header image is literally the welcome mat to your site. Because of its visibility it is worth spending a little time and effort on it.
Header images can be a photo, your logo, or basic text, it’s your call.
Remember, your visitors are arriving with very explicit expectations and your header should immediately identify they are exactly where they need to be.
This website uses the Genesis Daily Dish Pro theme. The reason I like Genesis is they have customizable headers, and header widgets so its easy to add elements in front or in back of your logo.
Note: Most Genesis themes by default do not offer full-width headers, however, it is ultra easy to install a full-width header by following this tutorial. (Note: Your full-width header will be completely mobile responsive.)
Remember, you can create a header image in Microsoft PowerPoint or Apple Keynote.