" Is this document aimed for export to a specific backend," - NO
" or is it just the way you want the org buffer to look?" - YES

The org-mode is a fantastic tool the way it is. I was just enquiring whether it is possible or not.

In one of my document I have to write few lines like "The following case is applicable only if you want to do this or that." and then a tree structure which instructs something.

Orgmode is powerful enough to design the document in a way to meet the objective. I will think about that. Thanks to all of you.