Brave was another Pixar masterpiece so the idea of more presence of that film in the parks would be a welcome one. Although, I recall during a press junket of some sort John Lasseter was asked during the height of Tangled's popularity about seeing more of a presence of the film in the parks aside from the meet and greets and he stated nothing was planned as of now. Personally, Tangled was one of the best Disney animated films in the past decade for me so it would be a delight to see the film more represented in the form of attractions. That said, I like the stance that Lasseter took where they weren't trying to rush a good thing. I think it's wise to have a film simmer for a few years to really allow the timelessness of it to sink in. I think Tangled will certainly make the cut to see attractions of some sort created from it in the near future, the same goes for Brave. Would I love to see attractions or shows based on these films? Without a doubt! I just don't think they need to be rushed in order to capitalize on the strong box-office numbers and great word of mouth the films have generated. In time, I think people's everlasting love for these films will do most of the work and we'll see something developed.
In regards to seeing Brave characters/attractions in Adventureland, not a bad idea but personally if there's one Disney film/character that is dying for a true presence in Adventureland it would have to be Tarzan. There could be a lot of potential for a really great ride system based on that film. I can easily understand how Merida's personality would fit more in with Adventureland but I recall reading from press junkets and interviews with the creative team behind the film that she is actually being welcomed as a true Disney Princess so that's why I'm slightly more inclined to see Brave pop up in Fantasyland if anything.