Although Google Draw is far from being my preference for requirements gathering/modelling, the ability to have direct comments / communications “right there” on the diagram, linked to anything on the diagram: I love that.
https://sites.google.com/view/tiddlywiki-portal/analysis-of-portal-requirements
Comments / suggestions via a form is the next best thing.
Either of these facilitate simple task management: information provided is useful not just because of where it is (proximity), but because of what can be done with it (multi-purpose without having to copy/paste it somewhere else.)
“Portal” aside, all of this is really interesting stuff from information/content/knowledge/document management perspectives.
What the link to the portal page above does not show is that “right there” communication, which we see in the screenshot below.
Cheers !