Tears of the Kingdom is full of areas to explore, so it's inevitable that one section seemingly falls flatter than the others. Initially, the skies far above Hyrule may seem to be the straggler compared to the mainland and the dangerous and dark Depths below when it comes to being dense with things to discover. But the seemingly bland environment of the Sky Islands works in their favor.
Starting out in the Sky above Hyrule immediately brings attention to the environment of the entire area. Having the Sky Islands feel so distant and empty adds to their mysterious quality instead of detracting from the overall experience. The islands are very spread out, making it both challenging and scenic to traverse the sky. The strange lands high above the land of Hyrule fit perfectly with their connections to the Zonai and as a counter to the Depths.
The Strength of Simplicity
The influence of the Zonai is heavily present in the Sky Islands. The most notable attributes of the Zonai are their technological advancements and the fact that they've all long since vanished. The environment of the island helps reinforce this somber tone. Ancient ruins jut up from overgrown islands while Constructs run about aimlessly, unaware that their creators are long gone. The environment is enticing, a little dangerous, and appropriately wondrous, making any trip up to the islands feel like stepping back into the world of the Zonai.
Besides the thematic appropriateness of the Sky Islands being quiet and lonely, the general stillness also accentuates the challenge whenever random boss fights appear. The same goes for the two dungeons that are found high above the domains they correlate to, with the image of a King Gleeok or low-gravity Flux Constructs immediately catching the player's attention in the sea of clouds and sun. Lynels and Hinoxes along the ground level of Hyrule dot the map sometimes unceremoniously, but every mini-boss found in the Sky feels intentional.
Above as the Opposite of Below
The Depths and the Sky add literal layers to the Tears of the Kingdom. While each area has its own gimmicks and challenges to traverse, the more enticing elements of both are the secrets they hide. In the Depths, valuable Zonaite and undamaged weapons hide around every corner in the dark, along with monsters that threaten Link with temporary permanent damage. The strength of the Depths is how dangerous and large any given section feels, and the darkness that blankets unexplored areas is the key to it all. The Sky Islands have a completely opposite approach, yet it works just as well.
Every secret hidden in the Skies, whether it's the ancient text islands, maps to treasure elsewhere, or Zonai weaponry, is placed in plain sight for Link to find a way up to. In spite of the obvious visibility of anything the player might want to explore, the feeling of curiosity is just as strong as it is in the Depths. In the Depths, the player is exploring blindly in hopes of finding a hidden reward. In the Sky Islands, Link must pinpoint an obvious location of interest and work out a way to get there. The danger of the Sky Islands is more specific than that of the Depths as well. The Depths uses the fear of the unknown, while the Sky's danger is very clearly falling off and losing progress. The transparent sparsity of the Sky and the claustrophobic density of the Depths complement the re-emerging world of Hyrule perfectly.