Obviously more muted colors will be more serene and subtle while bright, pure colors will be more dramatic and really make a statement. I believe it all comes down to two factors; your personal taste and room size. Once you decide on what color(s) to use then it's time to figure out which finish is right for you, your family and your house.
Sponging on-applying different color paints with a sponge to a uniform-color base coat. Adds depth to a wall. Perfect for a child's room to hide smudges or hand prints or on an imperfect wall.
Sponging off-laying down a solid color base coat and letting it dry, then rolling on a layer of glaze and blotting with a dry sponge to remove some of the glaze. Adds depth & complexity to a wall and is a little more sophisticated.
Ragging on-adding a nonuniform glaze to a uniform base coat. Adds depth to a wall. Great for kids because it looks informal playful and hides dirt.
Ragging off-similar to sponging off; you apply a solid-color base coat and allow it to dry, then apply a layer of glaze and remove some of it before it dries. Adds depth & complexity to a wall. When you want a diverse texture that helps conceal an uneven surface.
Frottage-using the ragging off technique but with newsprint instead of rags. From the French word meaning "to rub". Frottage using a plastic sheets or bags produces a faux leather effect. Adds depth & sophistication to a wall. When you want a diverse texture that helps conceal an uneven surface.
Colorwashing-create an aura of antiquity by casually & lightly brushing translucent coats of slightly differing color over a base coat. A subtle patina finish. Sophisticated and elegant. Or dilute white latex paint with water & color wash the ceiling and walls to give an old Fresco look without textured paints or glazes.
Dragging-dragging a dry brush through a wet glaze that has been applied over a base coat of the same or similar color. The look of fine linen. Sophisticated.
Combing-apply a solid-color base coat and allow it to dry, then apply a layer of glaze and comb to reveal the base color. Effective in small spaces and above wainscoting for the look of wallpaper.
Random combing-apply a solid-color base coat and allow it to dry, then apply a layer of glaze and comb in random directions about 6" long. The base color comes through only in these spots. A contemporary finish.
Stripes (vertical)-can be sophisticated or fun and funky depending on color choices, width of stripes and variations in width. Narrow, more precise stripes tend to look dressier than wider ones. Wide stripes visually expand a small space.