It will be great whenever the BIM exchanges get working.. which is still a pain..
for your interest have a look at osarch.org
Some are doing great stuff in the open source world.
And a working BIM exchange is to my mind only possible under the Open Bim premise.
So is ifcopenshell THE reference to me.
BlenderBIM can edit ifc directly !! IFC authoring that is new. The help of Graphisoft is wellcome.
Lukas