Small update..
I did "upgrade" my workflow with free software only. Because is think all the software available at the moment is just awesome.
But i will continue my small asset package for AF.
I tried a lot of things to optimizing the output of models through blender, i think this extra step should be taken by AF itself. So i am looking forward to the next version.
Another work around would be to create custom blocks ..
more optimized. As you can see.. it is the front side. Instead of trying to make all sides visible at all times (depends on the model)..
..the backside of the "custom_block" is just one (face-)sided. Yes, you need at least 2 pieces for both sides (front and back for a wall as example) to be visible, but even with that, you can safe a lot of geometrie.
It is also very flexible, because now, you can mix the in and out sides of walls.
The corners are fine, because there are no doubled faces. I hope you get the idea ;)