>>517
Part of the reason to use a limited palette is so you don't fuck up and start going crazy with chroma. When you introduce a high chroma color, it's very easy for your other colors to slide towards that chromatic color and everything ends up oversaturated around one hue. It sounds very basic but when you introduce a chromatic color, find nuances of it where it's cooled off by other colors and keep in mind where the cooler/grayer colors in the overall picture are to knock things back a bit.
As an example, here's a digital doodle I made a while back where I was trying crunch down my values and instead play a lot with broken color. Notice how every time a color is introduced it's cooled off by another color. Green is cooled off by purple and vice versa. If you don't pay attention to the other side of the color spectrum, it's very easy for your painting to slide to one color or becoming over-chromatic.
If you're doing things traditionally, spend time at your palette and make sure you have a range of high and low chromatic colors already mixed up because colors can slide even more when brush-mixing. In general I find it way easier to get good colors out of oil paint but maybe I just have a knack for it. Have several of the same brush when working so the brush with cad red in it doesn't have to pollute your white or something like that.
If you want to learn about color, the best book I've found is "Oil Painting Techniques and Materials" by Harold Speed. It actually talks about color in a meaningful way unlike Gurney or whoever.