>>57904244 (OP)>Gen3 Hoennpeak
>Sevii Islandswasted potential but still great and the 2nd longest postgame
>Gen6 Hoennshit
>Alolaok'ish to good, despite last island challenge being a complete empty hall
>Isle of Armorshit, as expected of a single island where most of your storyline revolves around doing tasks near the dojo where you start
Isles are great, specially an archipelago, but the question is if GameFreak gives each island its own map design, lore and purpose towards your storyline. Sevii Islands had the perfect map design and each island had its own lore, but most isles lacked purpose other than just exploring. Alola had isles with an ok lore and fully purposed towards the story, but the map design had similar problems to XY where caves where straight empty halls, and the worst part was that the last Island was a whole empty hall towards the island challenge. Gen3 hoenn was great all around and some of the environmental lore even hid some secrets that reward you in the end, although it lacked postgame to explore and some small islands were locked to events (Southern Island, Birth Island, Navel Rock, Lost Island) or special combinations like time and slotted pokémon (aka Mirage Island). Gen6 Hoenn replaced some lore secrets in order to give space to warped legendary encounters, and made multiple mirage islands that lacked any single trait possible. Islands are great, but it's up to Gamefreak if they don't screw up.
