1. A special type of a document sharpened for pre-defined fields (like a form). Of course, these pre-defined fields will be template variables. In other words, a special document without this big main body field and TinyMCE. I lack that in one section of my site called "meetings". Each page on it is based on template variables only (date & time, participants, small description, status, etc) without any other content. This confuses my editors, because they sometimes don’t realise that they don’t need to type anything in my TinyMCE and the template variables are located below.
2 (cosmetic). I think the name of the section "Template variables" confuses a bit. "Custom fields" makes more sense to newbie editors.
3 (cosmetic). Make "General" tab in "Create/edit document" page a bit smaller. I’d put "Link Attributes", "Menu title", "Menu index" to some +/- expandable javascript section (just like on this forum in "start a new topic" page, see "additional options"). The best thing would be, to let the admin decide which fields to hide under such section.