It's Netflix so I'll trust it'll be good. In fact, might as well have a Netflix Original shows thread because they've been hitting hard.
Why did netflix chose legend of zelda specifically? The series isn't known for its great plots. It's basically a good vs evil, saving the princess story. Whereas, the metroid series is way better for a TV adaptation, it has a better plot, it is more serious, and while, Samus was inspired by Ripley's alien franchise, the story is pretty different, Samus is a bounty hunter who is alone for the most part of the games. I know she's alone for the most part, shooting monsters and that might seem weird for a tv show but they can easily overcome that. I could go on with this but you know. I just feel like the writers would have a lot less to work on with legend of zelda and according to the para Will posted, it's going in a 'game of thrones' direction? If Legend of Zelda was a serious tv show, I'd think it would be bland as fuck As a kid's animated show, it could be interesting but this? eh. Okay, I'll stop now, maybe netflix has great writers who would take this series and write a great story based on this. After all, some of the stuff I said is a little bit of common sense, they probably have it figured out. And before someone tells me, its too early to have opinions on the show, okay cool.
Nintendo's said to be working closely with Netflix on this project. If it doesn't turn out how Nintendo wants, they'll scrap the project, because they won't want lasting harm done to their brand (especially not after that live-action Mario debacle). There's a lot of room for them to write an original, compelling story that doesn't necessarily have to follow the plot of any of the games. I think it can work out marvelously.
You say that there is hardly any material to work from but fail to realize that is a blessing in disguise. What it actually means is that Netflix and Nintendo will have a lot of creative freedom to tell any story they'd like without it resulting in the rejection and objections of their fanbase. They can very well craft a tight storyline within the confines of the universe that they created as long as they follow some already predefined themes of the series. Also, saying that there is basically no plot isn't actually true, as TLoZ history is such that there is an entire book to explain away its back story. This book is basically the bible of all things Zelda and is an official collaboration between Nintendo and Dark Horse. It is 274 pages of the histories and time-line and explanations of the Zelda universe. Though there are a lot of conflicting reports that quire frankly, do not make much sense, it is still the official word of Nintendo. There are also several official Zelda Manga/Comics that count as canon to the series. So, again, it's not exactly true that they have nothing to work with. They have a lot. But it's such that if they decide to go their own route and do more without delving into the accounts from the aforementioned literature, it'll be mostly okay because it is not widely known about and many are ignorant of its existence, meaning only the most die hard fans could complain. It's a win/win. The only thing stopping the TV Series from being good and watchable are mistakes/incompetence of Nintendo/Netflix. We already know Netflix to be competent in creating TV shows as far as direction/cinematography/production and sound go, so now we have to assume that the actual story being good relies on the creative minds from Nintendo for the most part.