Practicing negative space

I so admire the look of abstract paintings with negative space in them but it's pretty challenging for me. Here's one attempt! I like it!
Have you found a favorite brush yet? Also, did you like the chart for practicing with the brushes?
My fave is the Super Wet Painty!
I just gave out a freebie brush to newsletter subscribers that is painty and has a canvas texture but also smudges in a really fabulous way! You can always access old freebies you missed once you sign up so it's not too late to grab it! You can sign up on my site: https://www.leilaandpo.studio
Glad to see so many people enjoying class! I LOVE seeing your art!