Team building and forming a concept are good as well, and these do not come into conflict with what I said, in fact, they complement each other. Delegation of tasks, working with others, etc. are good things that would help projects get more progress. Forming a concept would be good as some of the bad game concepts on here tend to sift into shitty fan-fiction with stereotypical, generic Zelda stuff that makes the fan game itself seem even more unoriginal.
I have never developed a fan Zelda game (although at some point I do plan on it when I'm not quite as busy, which may never come to be considering the list of stuff I have to do). May I suggest some simple concepts of Software Engineering? I'm not sure if these would help for planning, but there really is like, quite a bit of stuff to know for planning and maintaining a software system that could potentially help for developing a game, such as requirements specifications, class/sequence diagrams, etc.
If that sounded completely stupid and unrelated to developing Zelda fan games, then just ignore what I said. Just trying to help
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