What kinds of themes you would want or be interested in? For example, would you like a header and matching icon for a boat theme? What about seashells? Fireworks? Wine? Horses? You name it (other than a fandom specific theme).
Tell me what kind of header, banner, or icon you would like, and I'll do my best to make it. Please let me know if there's anything you'd like to have personalized, such as any text you'd like on the header, or a name on an icon. If you have any questions just ask.
Just let me know what you want and I'll let you know if I can do it or not.