In many languages, subclauses and main clauses have somewhat different properties. The differences may appear in any number of subsystems - word order, morphosyntactical alignment, verb conjugation, pro-drop rules.
Sometimes, complexions exist - different types of subclauses may behave differently (relative subclauses being one reasonable exceptional subtype), and sometimes, subclause behaviors may also pop up in main clauses: morphosyntactical alignment, for instance, sometimes is ergative in all subclauses and in some main clauses with some TAMs. Verbal modes that typically appear in subclauses may also signal something if they pop up in main clauses.
If I have properly understood the terminology, deranking seems to be a term used to describe systems whereby a subordinate thing has distinctive features, such as the ones listed above.
My proposition is to have a similar distinction, such that main clauses with subordinate clauses (of some types) are distinct from subclauses and from all other main clauses. Maybe some specific 'superordinate' verb forms, maybe some specific word order (I would not be surprised if a superordinate clause has stricted word order!).
Subordinate clauses with further subordinate clauses would be considered superordinate as well, but could potentially showcase non-conflicting features from both, e.g. strict SVO[SUBCLAUSE] word order due to being superordinate, but ergative alignment due to being subordinate.
