It's good to revisit old works, time and again. I underwent such a project recently, the painting a 5 year old college project that was leaving many things to be desired. Thankfully, I was able to renew at least a small portion of it!
The original is a far more complex piece, in watercolor and acrylic. Retouching/repainting was done in Photoshop CS3 with a Wacom Bamboo tablet.