Bungalow floor plan - What should be considered?

That is exactly why people like to use [Raffstores] for thermal insulation:

Lower them completely, tilt the slats slightly or keep them horizontal: heat stays outside, light comes in, no artificial light needed, and you have a view outside.

What should be avoided: lowering [Raffstores] as well as roller shutters only halfway. For thermal reasons, this is supposedly not so good for the panes (stress due to temperature differences in the glass). However, I do not know to what extent this is also relevant in practice...

If the position were to be eliminated, then another company would have to return to the / into the masonry...

What I mean is that the construction company prepares everything so far that we can hire an external company to install a blind or shutter. Or am I imagining that too simply? Unfortunately, the construction company doesn't offer much regarding blinds or shutters. Unfortunately, the shutters are not rail-guided, which is what we would like.

From my layman's perspective, it should be possible. We are building with an architect, and the trades are also awarded separately. It just requires very good planning and coordination, I would say, but it should be possible from a technical point of view. But as I said, this is my idea as a client, not that of a planner/expert...

The shading trade must definitely be planned and executed in collaboration with the window installer and the subsequent trades!

The venetian blind slats can of course be adjusted so that at least no direct sunlight enters the house; diffuse light is always present.

The view to the outside is then naturally obstructed.

If needed, there are venetian blinds with daylight setting, where I have glare protection at the bottom and light comes in from above.

This is important for desk workstations behind it.

If the position were to be eliminated, then another company would have to work on the / in the masonry again...

Oh, that's what you mean. Roller shutter boxes are usually installed, except where no roller shutter is planned (bathroom and the like), regardless of where you get the window installer and the roller shutter installer from.

Unfortunately, the venetian blinds are not rail-guided, which is what we would like.

How else should they be guided?

There are cable- and rail-guided systems.