I have been working on my SMN ARR relic and I do feel that the ARR zones feel much more lively for me. There seems to be less purpose to the design and a more organic feel if that makes any sense. Ultima Thule is a great example of a map that was designed solely for one purpose, to serve the MSQ, and little else. It's laid out so you can only progress a certain way through MSQ blocks and once you can fly it is little more that 3 islands with some quest NPCs on them. The shroud though has all kinds of buildings and areas that are there just because they feel like they belong there.