I would like to see a Crop Region for Drafting Views, but I'm not sure that all of your examples make sense? 18 have already voted for this, so I may be wrong (please clarify, if so).
Personally, I would like to see it to be able to control crop for a linked-in .dwg file (though it's been a while since I've needed that, and there's a WISH specifically related to it: http://forums.autodesk.com/t5/revit-ideas/preserving-x-clip-of-imported-dwg/idi-p/6470908)
Since you're mentioning putting one detail on multiple sheets, it sounds like you're also asking for the ability to make Dependent Views of Drafting Views (since while Legends can be put on multiple sheets, only Dependent Views can have the same content with different Crop Regions)? Could you show examples? Maybe a Screencast of the workflow? I'm not understanding your scenarios. Thanks.