The importance of shooting raw is the tricky white balance issue which I rather to refine it in my raw developing process, also, the raw development gives me a better control on the right sharpness, contrast, and the balance between shadow and highlight area. With all these available adjustment there, I can then more focus on getting the exact composition I need because I typically don't crop my images - something I tried to avoid, although it is perfctly fine and acceptable for me to crop an image, I do sometimes, I don't do it often just because it is persoal preference.
An important reason I prefer the M "manual" mode is because I rely on my own preference of exposure very much, something I nicknamed it "TTE". So what is TTE? The who familiar with modern SLR/DSLR perhaps all know TTL refers to Through The Lens, an exposure system pioneered and first seen on Topcon RE Super, first exhibited at Photokina in 1962. Alpa 9D soon followed, then the Pentax Spotmatic and then virtually everyone else. And "TTE"? Quite simple - it is referring Through The Eyes. And the central of my TTE system is very much base on Sunny 16. Then, depends on how the actual weather, one can adjust the exposure value accordingly, and all these, is base on how one sees the object. This is to say, if there is shodow, let it be shadow; if there is highlight, let it be highlight. No metering system is better than hyman eyes.