[barrystaes]

This +

Layer one also explicitly identifies stakeholders, and describes the current (AS-IS) situation with annonated screenshots so everyone quickly sees what we are talking about.

Layer two also lists alternative solutions considered and why not chosen.

Layer three is developers making a few notes on chosen tech design, most important is the choice reasoning here.

In all layers, add and use references. Less is more, a picture beats a wall of text.

[nickm12]

Yes, agree with all of that. I don't think every design doc needs every possible section, but if readers would benefit from the background or the an enumeration of stakeholders, that belongs up front, before the design.

[j45]

Definitely - some sections are a bare minimum while others get activated based on complexity or need.