Not a bad idea at all. I recommend making the front door a color that is not used elsewhere on the front of the house so it becomes a focal point.

You can pick some of the colors from the brick if you're looking to coordinate more. You can also pick a brighter color (teals, purples) as long as they don't fight with the brick color. The siding and trim are neutrals so most any color will go with them. The nice thing is that you're only talking a quart of paint so if the first color doesn't thrill you as much as you thought it might it won't cost an arm and a leg to change it, just another quart.

Sounds like it's time to hit the paint store for some samples. Have fun.