Wow, it’s Mr CLAHE! It is one of the methods I have in my toolkit and have tried it as preprocessing in two Kaggle challenges (unsuccessfully, but beside the point). Thank you.
On non-photographic (non-ImageNet’y) tasks, it is often worth trying various colorspace and channel mixes to see what works best. Particularly if you have 4 or more channels of data (eg NIR), and working out how to combine those into 3.
Even on photographic images, other colorspaces often have a knack. e.g. Some say YCbCr is a better starting point for shadow detection. Color space changes are not the first thing I’d try, but they are an arrow in the quiver.