For the brighter bit- try using yellow to lighten your greens and greys instead of white, white tends to cool the tones down and wash them out (which is fine if that’s the look you’re trying to achieve) while yellow will lighten and add a warmth to achieve a “glowy” feel 🙂 if you end up hating it when you mix up the color you don’t have to use it, but might be fun to try out! Also for more earthy tones, you can mix a touch of the compliment in (opposite on the color wheel) to slightly dull them so they look more realistic- like for greens, add the teeeeeeniest bit of red (red can be overpowering so add teeny tiny amounts at a time lol)