I myself am guilty of running a number of projects at the same time, which can be stressful and irritating if done incorrectly. I recommend having two storygames at a time, allowing you to move back and forth between them to give those creative juices a good workout. Also, taking a break after working hard on your storygames is an advisable thing to do. If you're focusing too much on planning out exactly when you're going to publish your storygame, it can lead to stress and lack of interest if you fall behind.