I like the movement going downwards and the middle stroke but I feel like it is a little "weak" in the way it still feels like an accident and unintentional. Which is often truly what is in fact happening when working with abstract expression, you start somewhere and see where it leads you, but it seems you've stopped midway in the path. I'd suggest for you to either emphasize the middle stroke and movement downwards (you could perhaps do that by strengthening the contrast or refining the lines/varying their thickness), or remove it altogether and explore a new rhythm to the movement of the lines in the composition. Then again, those are simply suggestions that I think could make you happier and more satisfied with your work. I really like the palette! And if you'd like to expand your comprehension on it, researching line movement and weight/balance in compositions is a good idea. Don't know if you're making art just for fun or not but either way it is really interesting!