This is absolutely incredible. I had a busy weekend so only just seeing these updates from the last couple days now. As for it being open world, that was my ideal scenario, and Unity takes care of things like LOD and stuff for us, so going open world would actually be really easy assuming all of the scenery was aligned and scaled correctly.
As for not knowing Unity, that's fine. Getting the assets done is the hard part I think. Once they are imported it's just a case of aligning them to make an open world and then programming in some sort of dynamic loading so we don't have to have the entire world loaded at once (no point having Esthar loaded when we're in Balamb). There's plenty of people familiar with Unity so if you personally are not, don't worry, focus on a different area such as the environments like you're doing now.
I've been completely blown away by your work Maki so if you want to go ahead with the fishing pier I'd have no problem with that. Alternatively, if you'd rather have a discussion about that, we can, and like you mentioned, the interiors could be worked on next. If we can get the entirety of Balamb Town done that would be a perfect place to move on from environments to things like props, characters etc I think, then we can make a demo using Balamb Town. Demo doesn't have to make sense in terms of plot, but we can get something going such as NPCs, interactions, quests, random encounters, boss encounters etc just to show it working.
I'm super excited