Statement of responsibility - since expanding this is less work than providing added entries I expect we will decide to transcribe the full statement. Whilst we would always want all access points to be justified in the description, the reverse does not hold - we'd be happy to see names listed without providing added entries.
Related works/expressions/manifestations - I have to confess to being unsure how RDA is different from AACR2 in terms of access points for these. We would often have provided added entries in AACR so would continue to do so. I haven't managed to configure our LMS to turn these into useful links, though.
Relationship designators, while sometimes hard to get right, seem to be one of the potentially most useful elements of RDA so we do try to add these when editing a downloaded RDA record.
University of Reading Library, UK