Other members could respond to the responses by creating child pages. Graphics are handled by uploading to another server. I know this isn't as nice as Manila, but it was easier to implement, and allowed me to give that capabilty to my users sooner than if I had tried to roll it in. There are several macros that allow inclusion of images in a page. Membership is local to the site, and is sysadmin controlled.
Security uses browser-based authentication rather than cookies.
They can edit any page but cannot access the site administration features. Think of this as somewhere between Manila's Contributing and Managing editors. We want a little more control over this. Editors, however, can log in from anywhere. Only plain-vanilla members are excluded.