I'm a little surprised that this topic didn't already exist...
I find it interesting how you feel that the game is vastly different from LttP. Myself, I think pretty much the opposite. The game was a little too familiar for me, because I already knew so much about it from playing LttP. I already knew how all the mechanics worked, I already knew how to fight nearly all the enemies, I already knew the world map and made pretty good guesses where all the secrets were... There was very little sense of discovery for me.
The tool rental system adds to this as well. It means that I knew all I'd find out in the world and dungeons was rupees. I like the idea of being able to go anywhere a la Zelda 1, but I think the answer would be something more along the lines of not requiring items to traverse the world map instead of just handing Link every item in the game.
For me, the dungeons are the only good part of this game. And they are really good, some of the best dungeon design in the series. They made putting up with the rest worthwhile. Only thing I could think of in terms of dungeons is that I think there should still be an intended order (again, like Zelda 1), but you can do most of them in any order. I didn't feel like the dungeons had a difficulty curve, and with one or two exceptions, they felt like they were all about equal in difficulty. Which meant that the game got easier and easier as I went on. I know that's typically how a Zelda game goes when you get more hearts, but it became like, a total cakewalk.
I really like a lot of the ideas behind this game, but I feel it wasn't executed well. I would like to see these ideas tweaked and expanded upon in the Wii U Zelda title, though. There's good stuff here, it just needs to be a new game instead of built from an old one.
(Slight ending spoilers below)
Another thing about Ravio is that he's dressed as a bunny. A clear nod to Link to the Past and what happens if Link enters the Dark World with no Moon Pearl. This one was more clever, but still, it makes it somewhat easy to figure him out. I would actually like to see some New Super Luigi-style DLC that starred Ravio, and it would focus on his quest in Lorule to collect all the items he sells to Link, then find his way to Hyrule. The DLC would take place entirely in Lorule, and the world map would be the same, but it would have new dungeons in the places of the existing ones. I think that'd be pretty cool.