Having now for the first time taken a close look at bf:Title, I'm a bit taken aback.
1) http://bibframe.org/vocab/titleValue.html: "Title being addressed."
What is the purpose of this specialized property in the face of the bf:label that is available to all bf:Resources? What would cause someone to use it? Is this just MARC 2045$a in a new format?
2) http://bibframe.org/vocab/titleQualifier.html: "Qualifier of title information to make it unique."
Working for the uniqueness of labels goes very much against the practice of Linked Data. The Title entity is already possessed of an identifier. If anything more is needed to ensure uniqueness, isn't something badly wrong with the identifier?
3) http://bibframe.org/vocab/partNumber.html and http://bibframe.org/vocab/partTitle.html
Is there any purpose to this distinction or is this just a case of MARC 245$n and $p being mechanically preserved? In fact these two properties have the same range.
4) http://bibframe.org/vocab/formDesignation.html: "Class or genre to which a Work or Instance belongs."
http://bibframe.org/vocab/titleAttribute.html: "Other distinguishing characteristic of a work, such as version, etc.."
These seem very strange to me. In what way are these properties of a title at all? Is this just a mechanical transfer from MARC 245$k and $s? This seems to be information that should be recorded on the Work or Instance.