Check out the new blog banner header I just added it's free from Header Spot.
They have over 500 banners to choose from.
And if you do decide to change your header here's my advice.
If you go to Edit Layout and click on Header Edit.
Then you can choose shrink to fit and Placement Behind Title and Description.
Also you can change the colors of your Title in the Fonts and Colors section.
Maybe I can get my dh to help me figure out how to make a video
and I'll post it later for my more visual readers.