At the recent Canada on Rails conference Robby Russel introduced his upcoming plugin, Acts as legacy. Facing a 60+ table legacy system, I will definitely be watching that space. Acts_as_legacy would allow me to not worry about our existing scripts and jobs, while still rolling BiQ onto the rails.
For now, though, I am still partial to the idea of changing my tables around. Mainly to spare my poor fingers from having to type out stuff like intRelationValueRelation when building queries. relation_id makes so much more sense.