Channel content in structure
I finally found out craft allows multiple entry types. So a regular "structure" page can be of type "page" or, eg, of type "listpage". 

I created the second entry type and gave it a field function instead of the content.

In my regular structure page, I did the following:

{# switch between content pages and list pages; if list page, display selected list #}

{% if entry.type == 'listpage' %}
    &lt;article class="content-element"&gt;
        &lt;h1 class="heading-content-main"&gt;{{entry.title}}&lt;/h1&gt;
            {% switch entry.function %}
            {% case "interviews" %}
                {% include "interviews/_list.html" %}
            {% case "researchprojects" %}
                {% include "researchprojects/_list.html" %}
            {% case "seminars" %}
                {% include "seminars/_list.html" %}
            {% endswitch %}
    &lt;/article&gt;
{% else %}
    &lt;article class="content-element"&gt;
        &lt;h1 class="heading-content-main"&gt;{{entry.title}}&lt;/h1&gt;
        &lt;div class="rte-content w-richtext"&gt;
            {{entry.richtext}}
        &lt;/div&gt;
    &lt;/article&gt;
{% endif %}


Great!