If the clamor of too many noisy bits comes about from your desire to portray the complexity of part of the subject, consider first painting it as a single entity - a forest rather than many individual trees, or a crowd rather than lots of separate people. Start by looking for what the components of the collection have in common. Combine them into one shape with a wash of a "common denominator" color. Make the wash wet enough to stay wet while you add strokes to represent the units that make up the collective shape. Use thicker paint for these strokes than you used for the overall wash. The marks will stay where you put them but their edges will soften. Add subsequent layers of these soft-edged marks, introducing more colors and getting darker as you proceed. The idea here is that when the overall shape has a hard edge, but the shapes within it are soft, we will still see the main shape as one thing. The complexity is implied rather than specified.
As soon as you see a hard edge, STOP! Maybe you're done. At least consider the possibility. If you still feel the need for more complexity, you can wait for the painting to dry completely, re-wet it, and continue making soft-edged shapes.
here are a couple of images that have passages that could be treated this way. Look for adjacent shapes that could be combined. Do your best to keep the edges within the larger shape soft, unless you see the need for hard edges. Have fun.