More to explore:
Free Watercolor Smudges – Vectors, Textures and Brushes
12 free watercolor textures and backgrounds for digital design. And they are royalty free!
Free Hi-Res Canvas Textures For Craft Projects
PS brushes to enhance type and photos ... don't have a board for that specifically, but probably not a big deal.
Download 25 Free Colorful Grunge Textures