Matt, let me start by saying that this is a very powerful and well thought out composition. It has a "radial’ look to it that is very dynamic. And to me the strongest leading line is not the logs, it’s actually the rocks, on both the left and right. As @Ed_Lowe said its very much worth investing processing time to get this “right”, even if you decide to start over.
I think you have also gotten some outstanding advice from @Lon_Overacker and @Brent_Clark on local vs. global adjustments for exposure and contrast, and on adjusting color. I see from your response that you already use luminosity masks, so you have the tools needed to face the kind of challenges that you encountered in this image.
Mixed light like this presents challenges, there are areas in the scene that should be warm, (generally highlights), and areas that should be cooler, (generally shadows). When you try to just process WB globally via Temp/Tint in Lightroom you will never find there is one “balance” that works well for everything. Instead, try to approach WB on a local basis using Luminosity Mask selections. If you use the TK panel, make a Lights 2 or Lights 3 selection and increase warmth via Photo Filter or Color Balance adding yellow. Make sure your deeper shadows (especially green shadows) remain cooler, you want to avoid making shadows too warm by using global increases in warmth. Greens in shadow are naturally cool. You can use the eyedropper tool to measure shadows, make sure they have more blue. Here is your original post with some key eyedropper measurements
I like to take readings on what should be neutral colors to evaluate for color casts (either naturally created or processing induced). The three reading of the white water tell me that you have naturally mixed light in the scene. The left most reading is a relatively neutral white, the upper one is a bit warmer (both these points are receiving more direct or indirect sunlight), and the lower right reading is cooler (and it is more shaded), but it has a definite green color cast. These readings confirm that you have mixed lighting here that require local and not global color adjustment. You do not necessarily want to make each or any of them of them neutral. Take into account the light they are receiving, for example. Personally I like cooler whites in waterfall scenes like this, which contrasts nicely against warmer sunlit vegetation. The lower right white water reading tells me there is a strong green color cast in that area, it may be natural from reflected light off the moss, or it may be processing induced. I would try to correct that, it doesn’t look good. Use your color adjustments for creative effect, as well to correct obvious color casts.
The readings on the two shadow areas tell me that you kept your shadow areas, and shaded greens, relatively cool, and I think your processing of color there is pretty good.
In terms of the exposure / luminosity of the shadows, I find using a TK subtracted Luminosity Mask can be very effective in lifting shadows without losing too much contrast. I typically start by making a D2 - D5 subtracted selection and use a levels or curves adjustment layer to lift the shadows through that luminosity mask. And often I will place that D2-D5 layer in a group, and paint on the group mask to bring the shadow lift into only the areas of the image that I want to. Applying it globally often does not produce the best results. Here is a rework with a D2-D5 lift applied only to the far right shadows.
