I'm old school, so my approach my be different than most. I find putting the attention into time of capture more important than PP adjustments and printing settings. Starting with good color makes it easier to end with good color. When I'm evaluating a scene for angle, I look not only for compostion, but color elements. Sometimes I'll add something to the scene to punch the color. This is an old slide trick. We used to add something red to Kodachrome or something blue to Fujichrome. With digital, you can use either.
Also, certain lenses simply render richer colors. Certain cameras also produce richer colors, which is one of the reasons I switched to Pentax a few years ago.
A CPL also makes colors richer, but I don't use them often because there usually is a trade-off of detail. Underexposing slightly also makes colors richer. If you have a decent camera and shoot at the lowest ISO, noise is not a problem. Attached is a fall shot I underexposed considerably because the colors were all muted and rather dull. I also bumped the red and blue channels slightly in PP, but only slightly. The less you do in PP the better. When you bump a color channel, for example, it doesn't just effect that color, but the hues of all colors.
For this shot, I also used a GND to enhance the sky, which became an intregal part of the shot. I've had this shot enlarged to 20X30, and it actually looks better on the wall than the dummed down version on this screen.