>>38733547>>38733686>>38733677>Mossdeep>Pacifilog>Sootopolis>Evergrande >the Sky Pillar>Abandoned Shipwreck>Regice's cavern>shoal caveThese are all important locations that can be found simply by ACCIDENT just by bumming around in the ocean. The sense of freedom and adventure that Hoenn's ocean routes boast is completely unrivaled in the series. I haven't even mentioned the currents and divable areas that encourage you to be thorough, truly giving you a sense of exploration.
For comparison, pic related is what Nu-Gamefreak is capable of today. To add insult to injury, this is the BIGGEST water section on a region based on fucking Hawaii. Truly pathetic.