A map will probably help you decide which ones from your many ideas you want to choose but you may get lost in the art of map making and never get to write any of them down in detail as a book ! Its a very addictive hobby...

Courage could be the right word if you mean you wont write it down because of fear - (of it being bad or it being too much work etc) - "resolve", "will", "determination" all similar in meaning where it might mean you wont do it because your too lazy or its too large a task or too much of a burden. Courage could well be the perfect word tho if thats what you mean. Your English is near perfect so don't worry about that.

Welcome to the guild.