I believe that when EPCOT Center was designed and built, it was one of the most beautiful theme parks ever created. Over time, this has changed as new parks have opened (Animal Kingdom, Disney Sea, etc...), but it also became less beautiful over the years as many mistakes were made with Future World. A few notable examples are the tombstones, the wand, the tarps, the Test Track canopy, strange colors on Innoventions, and yes, large unthemed buildings such as Soarin' and GotG. When each pavilion was designed, care was put into the look of the building so that it would reflect what the pavilion was about. SSE represents global unity, World of Motion was shaped like a wheel, Journey Into Imagination has the glass pyramids representing the limitless possibilities of imagination, and The Land has the now hidden because of trees Volcano shaped building, which represented an important part of nature.
Unrelated to Future World, in the past, when a coaster was built, typically it was designed to tell a story. Space Mountain, Everest, Big Thunder Mountain, and Matterhorn in Disneyland each do not have a giant showbuilding, instead they built the coaster in an iconic structure. I believe this could have been done with GotG as well, but sadly they took the cheaper and faster route, and built a generic box. Regardless of opinion about the sightlines, I'm pretty sure all of us would agree that if they built a structure that had a more iconic design, it would have been better for the park in the long term.