One of the few things I wanted to change was Wally's coldness. Rather than have him be in his mid-twenties, I decided he was about 18. This made his perceived reserve more like insecurity and survivor's guilt. After all, the closest thing he had to a father had just died, and his real father was a con man and minor criminal. I also began to play around with his mom. I didn't have much experience with angry, substance-abusing mother, so I let Wally's mom get softer around the edges, a little more like my mother. I brought back a couple of his villains – Chunk and Pied Piper – as heroes, on the theory that if bad guys never reformed, well, why not just tear their hearts out of their chests ?
You can read the entire essai in The Flash: 80 Years of the Fastest Man Alive on ComiXology.