I also did that exclusively with Elefront until R8 was out
then R8 shipped with a new set of GH components that allow a very good handling of baking, updating, retrieving and filtering geometries, layers, blocks, object properties from the Rhino document
so, in short if you are on R8 I very much think you can do all those things using native R8 components from the Rhino GH tab
In addition to the docs that Andy shows, here is the Rhino 8 components throwing objects on different layers and displaying with different colors. Material could also be assigned.