Creating effects in post generation

I'm wondering if there could be a way of creating effects post generation in Firefly. The image could be first created as a setup , like a posing and arrangement. The filters could then be applied after that initial generation. Things like lighting could be added  as needed ather than simply excepting what was added without any real guidence. It would seem that this might be a more productive approach. Perhaps there could be a choice such as add light after, or enlarge this, or move it?