To my mind the most important one is missing,
The Game Engine and its pros and cons as well as a list of editors and their pros and cons.
You can go around making the most awesomest docu trail ever but its absolutly useless if you do not know what you will be using to create this masterpeice.

Secondly, there is no listing of resources, people you could draw from for experience, ideas, jobs etc.
Third, you need a development timeline if you are serious about using this route with probable checkpoints, milestones et all and reviews.
Lastly, you need a budget ! Got to have a BUDGET!

By knowing your dev engine you also know what it can and cant do and so you have parameters set for you. You also need to know if further costs are to be added (licensing issues) or if you need to write dynamic link libraries, plugins etc. to get around some of the shortfalls the engine may have in its present state.

Hope this adds some thought to the pool,
Later...