Habitat base design strategy in Subnautica

Question

I am a beginner at Subnautica and ready to build my first habitat.

However, there seems to be two different ways to do that. I could build stacked multi-purpose rooms. Then I could put corridors branching off from the MPRs (can you do that?)

The other option seems to be to build one or more foundations and then build corridor type modules in a matrix on the foundation.

What are the main considerations for different habitats such as these and how should I approach it?

Answer 1

Then I could put corridors branching off from the MPRs (can you do that?)

Yes, you can branch off corridors in 8 different directions, but in practice you will usually branch out in 4.

What are the main considerations for different habitats such as these and how should I approach it?

Location, location, location!

Your habitat needs energy. At the beginning of the game, the most available energy source are solar panels, which give you a reason to build your habitat close to the surface.

But you are also going to need space. You will want to expand your base a lot. Not because you have to. The things you actually must build to complete the game aren't actually that many. So a tiny base is actually viable. But you will want a larger base, because you will want some space to arrange containers to organize all the resources you are going to hoard and to place all the cosmetic items and furniture you are going to collect. And no habitat is complete without a mostly pointless but awesome looking multi-story alien containment tank. The resources you need to expand your base become pretty plentiful during the midgame, so there is little reason not to.

In the midgame, you will unlock a very important room: The "moonpool", a rectangular room which allows you to dock vehicles by entering it from below. This is a very large building (a bit larger than two MPRs next to each other) and you want plenty of space below it for convenient vehicle access. So if you plan to keep your first habitat, you should plan for where you are going to build your moonpool from the beginning. So it makes sense to build the habitat on the edge of a cliff, so you can place the moon pool hanging over it.

Foundations are not really as important as they appear at first glance. They are mostly cosmetic. They can be used to increase hull integrity in the early game, but as soon as you get deep enough to collect Lithium, that purpose is taken over by the far more powerful and less intrusive Reinforcements which you can slap onto any unused surfaces of your habitat. Another purpose of foundations is for placing outdoor grow beds near an entrance of your base for convenient farming of water plants.

My approach in my second playthrough which I found pretty convenient was:

1. Start by building a provisional base next to the lifepod, consisting of a single I-compartment, a hatch and solar panels on top. Its main purpose is to charge batteries.
2. Explore the world from that base until I unlocked multi-purpose rooms and indoor storage lockers and hoarded a waterproof locker full of titanium.
3. Build a proper base in a more spacious location. But still close enough to the surface to use solar power and not need too many reinforcements.
4. Deconstruct the provisional base and storage lockers and move everything in it to the new base.

Answer 2

This question is moot because it turns out that when you are in the early game you will not normally have access to the MPR blueprint, so you have to use X-corridors.

If you have played the game before and know where the blueprint is, you can contrive to get there, but it is kind of cheaty to do that.

Although the MPR is certainly a superior module, the X-corridors function adequately.