I've played like 7 hours of the game, it's pretty linear. Feels like FFX I don't think you should go in expecting it like The Witcher or Dragon's Dogma (maybe Dragon's Dogma but with the very empty stretch being cut out)

So far I've visited 3 areas. The first one is a tutorial area, short. The second one is more corridor-y, but longer, with more enemy encounters. The third one is wider, less corridor, there's a 'town' in the middle that's so far only for story beats.

All those areas are 'dungeons' to be honest. At this moment, I can't just select and visit those areas, but the game provides you with ability to replay those sections.

But again, all the sidequests i've done are tutorial sidequests, the game hasn't opened up yet.