You need to establish your brand, so no, clear and specific this time.
Once it's established you can recess a watermark effect into stationery so that your brand is there but it doesn't put folk off writing over it. I do this with my postcards, the drawing on the front, address details on the back and a watermark or recessed effect of their pub brand/sign into the paper....
Dear Dizmo, You can use watermark on your custom and your own created designs to stop other to stolen your work and share on their portfolio. Watermark shows your identity on your own work.