What data access architectures are available that I can use with Raven DB?
Basically, I want to separate persistence via interfaces, so I don\'t expose underline storage
What are you trying to achieve by that?
You can't build an application which makes use of both an RDBMS and DocDB, not efficiently at least. You have to decide for yourself which database you are going to use, and then go all the way with it. If you decide to go with an RDMBS, you can use NHibernate for example, and then again - no need for any other abstraction layer.