I know you put these brushes up a while ago, but this is an outstanding resource you have made, both technically and creatively. I love the chaotic nature of them. And, as you say, not only will they do for any sort of liquid, but they are really wonderful to employ just as texture.
Not really a critique but more a plea... it would be lovely to have a tutorial on how to employ these properly. I find the opacity and blend settings are less subtle in illustrator than in ps, and it would be nice to see some examples of the brushes employed.
Again, thank you for your generosity in sharing these.