@BootlegProfessor thanks for the kind words! Block quotes are coming in an update (as are code snippets which we are going to treat in a slightly related way).
The way we have modelled the document structure involves thinking about it as a construct made out of a section / subsection / …section tree + paragraphs and floating elements like figures, tables and equations that are associated with those sections. The presentation of each of the paragraphs etc is derived from a style, and presently we only have one style per semantic element type. This is the thing that is going to change: we are going to allow you to swap the paragraph styles within the category of elements. Basically, we want to still guard consistency at least to the extent where you don't become tempted creating headings out of paragraph level elements etc.
(A meta discussion point: It has been just suggested in another post that we start organising these "is X there?" posts into a roadmap like thread. I'll see if we do that or a separate category for the purpose as this is actually sort of a partial duplicate question already.)
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