Don't be deceived: the reason why these plans look nice is because of the team structure of the Zelda project. The design team spent a lot of time drawing up polished graphics and layouts and then "threw it over the fence" for implementation, in waterfall fashion. This is still a common practice within Japanese teams, as evidenced by, for example, Mighty No. 9's documentary, where you can witness an entire level cons…
you don't have bootstrap for game development... you better make sure the levels you spend time developing are well designed.
How can you be sure they're well designed until you've tried playing them?