I'm wondering how the world design of BotW 2 is going to change from the first game, gameplay wise.
BotW was based around having total freedom in navigation, allowing you to get to any place from any direction. The world had very few hazards or bottomless pits, you can get to basically any place in the game by paragliding or climbing. Exploration-wise, a big part of the game was wandering from one glowing point of interest to the next, taking light detours along the way to explore all the little areas. There is rarely any big chunks of content, you'll normally be done with each piece of content within a few minutes.
In BotW 2, we can see that Shiekah Towers and Shrines are completely gone. These were a significant chunk of the content in the game, and were normally placed near the most interesting areas in the game. These were key objects for guiding your eye towards different areas, as they were designed to be seen from a wide variety of angles and are clearly visible all the way across the map. With the removal of them (and the Divine Beasts), there's now much fewer points of interest. Even in the footage of the ground from the second trailer, we only see a few notable changes, such as the Deku Tree being gone or Death Mountain not being filled with lava. Apart from a few stone ruins on the ground and different placements of monster camps, the vast majority of the map looks the same so far, and would need some drastic changes to become interesting to explore again.
So how would these drastic changes happen? In Ocarina of Time, A Link Between Worlds, and Link to the Past you unlock a new world after beating 3 dungeons. This is easy because the games are linear, and every player will be in the same spot once they get the chance to access the new world. But imagine having something like this in BotW. BotW has no midpoint, the only points at which every players are on the same point are the very beginning of the game, the point at which you get the Paraglider, and when you face Ganon. It would simply be impossible for there to be a point at which the world changes shifts drastically, unless the developers were willing to have a before and after version of every single part of the game (which would be a huge waste of developer time for a world so big).
It is possible that the new game is really just going to be a retreading of the old map with a few new areas and scenarios. But considering that it's taken the devs 5-6 years to develop this, I have to imagine they have something major about the overworld that they haven't shown us yet, something much bigger then sky islands, an expansive underground, or underwater exploration. While I'm not quite sure what that change could be, I do know that the design of the game will have to be different then BotW 1 to accommodate that change.
I think the Sky Islands give us a hint at a possible new direction for the sequel. Instead of 1 large island in the sky, it's a bunch of different sized islands with large amounts of space between them. To navigate the sky islands, you often won't be able to brute force a straight path to your destination by climbing or gliding. Instead, you'll have to carefully glide from island to island, making sure to watch your distance and stamina to reach each island. If you are on an island that is lower then the one you are trying to reach, you'll have to figure out a way to get higher, possibly by using the new wall merging mechanic that shoots you upward. There are now essentially bottomless pits in the overworld, which wasn't often present in the first game (It is possible that you can fall from the sky islands all the way to the ground, but it would be really annoying to fall for 30 seconds just because you accidentally fall off an island. Also, the cloud barrier from from Skyward Sword is shown in BotW when the Dragons rise into a portal in the sky.) Overall, the navigation will be much more linear, but will require a lot more thought.
But what destination are you trying to get to get to when on the sky islands? While these screenshots only show a limited view, there doesn't appear to be anything noticeable like a Shiekah Shrine or a unique landmark...
...except for the giant tower on the right side of the last image. While this could be many different things, I'm thinking that it's a dungeon. It doesn't look like something you are supposed to climb. BotW had basically no explorable buildings (except for Hyrule Castle, which had several obvious entrances), so it's especially notable that the devs chose to show this building, knowing that most fans are hungry for more classic dungeons.
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On a separate but related note, there's a reason I talk about the sky islands as if it's all 1 area. Back when the second trailer came out last year, I did a little analysis of the sky islands to get a better idea of the layout. I found that the trailer only showed 2 areas which are likely pretty close to each other. It's a little scuffed, so just ask me if you don't understand it.
Some people think that the Sky Islands are going to be a major part of the game, but unless there are a lot of new sky areas that we can't see, it's probably a relatively small area that you could fully explore in just a few hours.
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Because of the more linear design of the Sky Islands and the presence of a possible dungeon, I'm thinking that BotW 2 is going to consist of areas that are centered around completing a main goal, which is to explore each region to find the dungeon (or find access to the dungeon). This doesn't mean that there won't be tons of side content and objectives to complete within these areas, it just means that side content and mini dungeons won't be the primary focus of the game like it was with BotW. One of these areas is the sky islands, while another area could be underground, the area where the Deku Tree was, or the crater of Death Mountain. These are all relatively closed off areas, so they fit with my idea relatively well.
The overall goal of the game could be to re-forge the Master Sword and kill Ganondorf, and the way you re-forge the sword is to get a special Mcguffin from each dungeon. If there is some sort of huge change that happens to the overworld (or an alternate world gets unlocked), perhaps it'll happen after you complete the first few dungeons. Maybe you restore the sword in the first 3 dungeons, which gives it the ability to make you travel back through time. And since you can't kill Ganondorf without the Master Sword (Calamity Ganon could only be destroyed by other weapons because it wasn't the real Ganon), so perhaps you won't be able to reach the final boss as soon as you leave the tutorial area. This works with a design philosophy that is based less on pure freedom and more on structure and progression.
Of course, I could be wrong about literally all of this, but that's part of the fun of speculating. I am still perplexed that the overworld seems to look almost entirely unchanged from the first game apart from a few relatively minor changes, but I hope there is some big twist that Nintendo is hiding from us.
. Sooo:
or more specifically that the new mechanic takes Link to their realm, basically serving as a portable Minish Door. Until insert random plot reason here and the barrier between the worlds breaks and the islands are noticeable from the surface.
