A LUT is like a music loop or sample within a song, it can contribute to a grade, but it shouldn’t BE the grade. Automatic correction is like autotune, it can solve problems, but it shouldn’t be the main flavor of your grade. Plugins are like audio effects, a bit can give music texture, but too much makes it look like you’re concealing problems.
If you want to practice grading as an art, and I do mean practice, you have to really put your mind and your heart into each scene, making creative decisions that blend myriad techniques together in the service of a creative goal. You need to learn to see the image without artifice, you need to learn to imagine what it could be, and you need to learn to bridge the two with practiced technique and a steady knowledge of your tools.