Hi Chris,
I'm a good candidate for this proposal because I'm a talented writer with English as my native language. I'm Irish but don't worry, I'm extremely familiar with American English and all its subtle differences. I'm suited to this particular project because I have first hand knowledge of the game and have been playing it since it was in Beta. I'm familiar with all the maps and the heroes and follow the pro scene.
As I was reading the description, ideas were already jumping into my head about how I could go about structuring the book. Starting from an overview on each hero, their strengths and weaknesses, what maps they are best on, what phases on maps they shine. For example, niche picks like Symmetra who's great at defending narrow choke points when on the defensive phase of certain maps, but is much less effective when on the offensive and needs to push past enemy lines.
I'd proceed to talk about the maps, giving a quick rundown on them and into more advanced tactical decisions that can be made on them i.e. abandoning certain positions, rushing, chokes, key areas to defend.
I'd include a general gameplay guide, focusing on individual skill improvement mostly on aiming, movement and also stressing the importance of communication with other teammates and team composition.
Another thing which is important in any online game would be a short focus on mentality and staying positive.
I hope you give me the opportunity to use my knowledge to write this book.