In some cases I want to switch design aspects on different pages.
Currently this is only partly possible (by putting
div class="group GROUPNAME"
in startgroup.pstl)

But sometimes a whole page needs another header, footer or color.

Giving each page an unique body class would make this possible. When each page is a group, it could be:
body class="groupidentification"
, this could even be an extra field on group definition pages, next to group name and group definition.

You could also do this on 1 question per page surveys.

For a noobie user it is not that easy to install this application as compared to other similar applications out there.