Writing because the words pour out seems a good reason. :D

You might want to consider Kristine Rusch's advice on how to do some indie publishing. You write enough that you might want to consider things such as Polychrome that don't fit the traditional market for such an endeavor.

I know you would prefer the traditional path and :D you even have an agent now so maybe that isn't something to do with your extra stories. But considering that you leak short story and book length stuff that is very fun and readable keep it in mind.