Recent experiments with hand painted journal covers have been productive. I have been using heavy recycled cover boards from discarded books and given them a new look with acrylic paints. The painting technique involves starting with a background color and then adding a variety of colors with 'found object' stenciling. Very fun to do and I like the playful results.
The front and back covers are painted at the same time to allow continuity of colors, but they are each unique in all other respects.
Here is another color variation using a violet base color.
The pages are a variety of papers, including watercolor, heavy illustration and high quality text weight papers. These would be perfect to use as visual journals.
You can find a variety of hand made books like these in my Etsy shop.