To create a structure to work in, we divided the different scenes of Remembering into Themes. Each scene is about a different part of conception and development of a human in the womb. So one scene could thematically be about the development of touch, whereas another is thematically about heartbeat (or the scary absence of heartbeat...)
By structuring our game into these themes we created a guideline for ourselves to match visuals and interactions within a meaningful frame.  In each of these scenes we experiment with different mechanics we wanted to try out. Throughout all the scenes we tried to tightly integrate the theme with mechanics and visuals.
Two examples:

The 'Forest'

Example 1. The 'Forest'
In the ‘forest’ we spatially deconstruct a musical arrangement. Every ‘tree’ contains a single violin stroke. Together they form a melody, but this melody can’t be heard because every tree only produces its sound if you look at it. So you only hear fragments that hint at a greater whole. Until everythings comes to live simultaneously in a crescendo.

We placed this mechanic in the scene that thematically describes Conception. Our associations with conception were about separate cells, each with it’s own incomplete identity, coming together and creating a more complicated whole, a human. We quite liked the analogy between separate sounds coming together to form melody, and cells fusing together to form live.

The 'Womb'

The 'Womb'

Example 2. The Womb
Towards the end of the journey you enter a scene where you are in a soft pink space that surrounds you on all sides. This is, of course, the womb. For us, being in a small physical space is also about that space being able to touch you.  So, here we introduced an almost ASMR inspired mechanic where we have objects stroking your ears, accompanied by sound effects that support that illusion. This being Virtual Reality, this physical illusion becomes that much stronger because you can actually feel your body being there, in this virtual space. A little later we take this feeling of embodiment to an extreme by thematically introducing 'pain' (your birth is imminent after all). We pierce the players body with sharp, black spikes. We see players actually grope for the affected bodyparts, as if they are pierced in  real life. On a thematic level this fits. Your body is complete. It exists (in VR), and you are aware of it now (in VR).
Now it's time to be born.