Would you be interested in getting your Grasshopper models into Revit via IFC? Geometry Gym have started looking at this using the Revit SDK. Quote and link below:
…with a few Geometry Gym users looking for a work flow to get Grasshopper models into Revit, I’ve been looking for improved ways to do this using the Revit SDK. I started looking at direct model interaction, but for technical and practical reasons have decided a neutral bridge is the best way to do this. Most of my c# IFC code is reusable (with some interaction changes) as a Revit plugin (this is my first plugin outside of the Rhino/Grasshopper environment), and I’ve today posted an example import of a steel frame roof (British Museum Great Court Roof) using my own IFC engine.
Geometry Gym: Revit IFC Plugin by Geometry Gym