I forgot to post this in my last post, so why not another one?
I put together 3 use cases for my web application. What are use cases? They are short paragraphs listing your typical users and how they will use the app. My use cases are for the three primary types of users that I envision. As I get deeper, I will probably add more cases, but will not be removing any.
What are use cases good for? They mainly serve to remind me that I have to put the app together in a way that is intuitive for the different types of users. They may be good at computers, or they may just be the email/surfing type. So every decision that I make in regards to design and usability have to work for these users. They are also part of the spec for the app, as the use cases flesh out the different things that the app has to do.
Micro Software Development 
You need to flush out your use cases. A use case is not a paragraph detailing everything an actor can do. It is specify individual actions allowed by the system, or any number of actors. They need to be generic enough to allow for flexibility, but specific enough that anyone could code.
For example, the use case for opening a door would look like:
Action: Open a door
Actors: Members of the household
Precondition: Member has a key
Post Condition: Door is open
Steps:
1: Actor turns knob
2: System opens the door
Alternative Steps:
1: Actor turns door.
2: Door locked, error returned to Actor
3: Actor inserts key
4: Actor turns key
5: If key is correct, door unlocks
6: Actor opens door