Well, there is an easy way out of both of your issues – header size and hiding the title (previous query). Just do the following for a page or a post –
https://docs.google.com/file/d/0B9j6FQo4cSQFUzl3bnNCOG1wbjg/edit?usp=drivesdk
The header image will reduce gracefully depending on available width and no title will be required.
As I suggested earlier, due to the image being foreground, header truncation does not occur. If you want title text, you can apply by absolutely positioning it inside this image.