Disney of late has not been great at utilizing all of the space available for attractions. The buildings and facilities keep growing larger and larger, while the experiences themselves don't gain any appreciable length or quality.
Just consider how massive the Tron building will be, with relatively little track inside. There are wide sweeping turns with lots of open spaces surrounding it. From what I've seen, there aren't lots of huge set pieces in there, it's just laid out in a way that leaves a lot of empty space between the tracks.
Now compare that with the dense tangle of track that was used for Rockin Rollercoaster. While I think that attraction is somewhat underwhelming for other reasons, it does a much better job of getting the most out of its building. The building footprint is only about half of Tron's (approx. 74,000 SF vs 138,000 SF), yet both have similar ride lengths (around 60 seconds, ~60mph max speed)
Given that GOTG is already relegating one of the largest showbuildings that Disney has ever built to just queue and load space, I see no reason to expect that the attraction will use the gravity building itself any more efficiently. If they were concerned about space, the building likely wouldn't be a monolithic box, but something more form-fitted to the track itself (which even Tron does to a degree).
This approach pretty much sums up why this project is so frustrating to me, regardless of whether the ride itself fits the park: if you must use so much space, have such intrusive sightlines, and spend so much money, you need to make sure you're using all of those resources as effectively as possible. Everything we've seen thus far indicates that they're not. It's just such a waste of so many things.