I live in an area where I have similar things to paint. Fall foliage can be really intense, and we have an number of creeks which at certain times go dry so I "get" this painting subject and understand why it attracts you.
To me the most glaring problem is your value structure. It is all mid tones.
Your color is lost because the value is lost. You show lights on the main tree and in the foreground, so light is available, but no where in the rest of the bushes or back ground groupings.
There is the same size banding of your colors through most of the image. This is an less interesting design than it could be. I realize you've varied the height of the foreground bushes on each edge, but the main tree branch bunching is reinforcing this height with the two edge bushes, and your lack of break in the bushes doesn't keep the eye from holding the mass as one.
As mentioned earlier, all the interest is on the left side of the painting. The tree is located at the 1/4 division of the painting. A small item in the background - could be an interesting spot of color could draw the eye across to the other side of the painting.
There was an opportunity to vary the lower edge of the brush - even if it isn't in your photo, it would have counteracted the line of the river bed (which I think needs more information since I couldn't identify what you were trying for).
Your trees don't read as real, nor stylized, just incorrect in their construction. If going for realist trees, the limbs wouldn't taper that quickly. The trunk on the tree in the background is thinner than the growth above it. The foreground tree is thinner below the branching and has a divot on the left side.
As before you have lights showing on this tree from below, from the side, from the front, and from above. I know you haven't asked, but since you include trees and bushes in your work often might I make a suggestion? There are two books I recommend heartily on trees which teach how to design and portray groups of them. They're both free and I refer back to them all the time. "On Drawing Trees and Nature" by J.D. Harding, and "Artistic Anatomy of Trees" by Rex Vicat Cole. The J.D. Harding book will give you ideas on how to think about mark making, foliage design, and designing trees. The Cole book is much more extensive on how to actually help you think about how trees grow, what makes a graceful tree vs an energetic tree vs a powerful tree vs a broken tree. He also gets into shape design with trees, groups of trees, and how to call attention to a tree in a landscape of trees, annnd gets into major tree types pines, maples, oaks, beeches and how to use each in a landscape.
Just my thoughts.