Hair color isn't always about just "color". It's about shades, hues, and a good cut that will show off your new color. Perfect color doesn't come in a bottle. If you are hoping to get a color correction for past mistakes (caused either by you or another salon), it will take a real expert to add in the right toners to counter the faulty shades you are trying to get rid of.
Even at home hair coloring kits have come a long way when it comes to being gentler, safer and more pleasant smelling. They too use far fewer harsh chemicals that can lead to damaged hair in a heartbeat. Making it safer for you to get the desired results. Which as hair color ideas go isn't a bad thing, now is it?