I'm looking for recommendations for software for managing authorities.

Currently we're using a somewhat antiquated version of EATS but we're looking for something 
different. Our needs / wants are:

(*) Sane import/export to RDA (leaning towards RDA native)
(*) Sane import from legacy formats
(*) Sane export to sundry RDF formats + legacy formats
(*) Web based
(*) Out of the box rather than highly customised software
(*) Good support for bi-lingual / multi-lingual entries
(*) Ability to host multiple entirely separate authorities groups with 
separate policies and practises.
(*) Explicit support for VIAF / wikidata / LoC

It occurs to me that conceivably the best software for the job is 
actually an LMS with all the item-level stuff suppressed in favour 
work-level and authority records, in which case the question becomes "is 
there a RDA-based LMS that can be customised to remove all the 
item-level stuff?"

Stuart Yeates
Library Technology Services