I use a similar similar process when developing characters. Most of my stories start out as individual scenes that I then figure out how to string together cohesively. After I'm done with the rough draft, I walk away for a month. At the end of that month, I go back an reread it with a fresh perspective. It's not unusual for me to add another chapter or two at that point, and (sometimes heavily) edit other parts. I also study psychology pretty heavily to help me better understand how someone with a particular personality would react to certain situations.
Everyone has their own method. My advice is to try on different methods for size to see which one fits you. What works for me, may not work for you.
