Forget about previous map... Now HauOli city looks...
From 100% sure things about Alola...
- First we need beat/catch Tapu-Koko to have acces to special chamber where pillars summon other Tapus.
- Necrozma was awaiting for you in Ten Carat Hill.
- By special Acces you have Ability to travel into PILLAR OF SUN.
-- In there special Ring Portal can take you to Another Dimension. Pillar of Moon
- Lunalla, Solgaleo, Necrozma, Tapu-Koko have their sprites in Overworld.
- Team Skull try interrupt us in the Ruins...
- Pokemon Rangers workings for Aether Foundation will fight with us in Pillar of Moon after obtaining Lunalla.
From Ideas... I think about make a little sidequest in Kanto Region. Magnet Train is in Goldenrod so I think to Activate it and give you able to travel into Saffron City...