For handpainters, always keep in mind the top-down lighting that League has. You will always have a dark gradient traveling upwards. Without this, champions can appear flat in-game. The farther their body is away from us, the darker it gets! As you make you custom textures, be mindful of that.
Take a screenshot of your champion in Maya and place them in a test scene against a Summoner’s Rift background with both a color and grayscale to help you visualize what needs to be done.
Sometimes the values can differ depending on what you are comparing to. Darker colors will obviously be darker in value, so you have to be especially mindful of gradients in those. Lighter colors are usually easy to catch issues in. In this example of Graves, I plan to make a darker purple color for the lower half of his jacket to help with giving a more convincing lighting situation.
If you want to learn more about custom textures and other helpful painting tips, check out the Substance 3D Painter Tutorial I’ve written on the website: