Minimum door spacing during floor plan development

In the shell construction dimension, we should plan at least 15 cm so that the frame still fits even with minor deviations.

If it is too tight, in my opinion, it doesn't look good either. We usually left 30-50 cm of clearance. I also find it nicer if the door can open more than 90 degrees.

The door opening should be more than 90°. Better yet, 10-15cm is, in my opinion, mandatory; even better is at least 60cm so that a cabinet can disappear behind it.

More than 90° is not necessary at least for us, since immediately behind it there is the wall. So the consensus is around about 15cm!?

Absolute minimum requirement: you want to be able to open the door fully. "Fully" in this case means slightly more than 90°, because when the door is fully opened you also want to have the door handle out of the way. So behind the door there must be the door thickness plus twice the handle depth plus a 1-2 cm safety margin for trigonometric effects. However, this is measured from the hinge, not from the wall opening. What this means in concrete numbers depends on the specific door-handle combination. In any case, if you really have to calculate so tightly, as it sounds here.

That is also a question of the door system used. With or without a handle, with or without a visible frame..

I once worked with an opening angle of 100°.

How much should the distance to the other side be? Would that be possible?