I agree. It really does sound like a good product. It is also, no question, a very specialized product. Highly useful for architects trying to design energy efficient large buildings.
But it doesn't have much use for an overwhelming majority of SketchUp users (I'm guessing here.)
And it's on that basis that I question it's status as the only extension (that isn't included with SketchUp Pro) to have it's own place within this forum. That's giving it pride of place that, IMHO, no $899/year licensed product (Trimble or otherwise) deserves.
I'm not saying don't talk about it. Just talk about it in Extensions with a "Sefaira" tag.
What's next? OK, Trimble Connect I could see as justified given the model sharing and communication with other platforms that it enables. How about other Trimble products? Will we be seeing every Trimble product with a connection to SketchUp receive it's own category?
What about popular non-Trimble products? There's certainly enough conversation about VRay on this forum - far more than (I expect) Sefaira will appear. Doesn't it deserve it's own Category? Assuming it costs Trimble (virtually) nothing to add a category, why not give every extension with over 300 downloads it's own category?
Back to Sefaira. It's one way that the beauty of keeping SketchUp focused on geometry modeling, while allowing 3rd party extensibility, manifests itself. And I think this forum should stay focused on this core competency.
Perhaps there should be a policy of adding specific extensions as 2nd level categories under "Extensions" once a threshold of use is crossed. Perhaps 500 downloads and 30 forum threads? (That came off the top of my head.)
Now, if Trimble starts including a Sefaira license as part of the SU Pro, my feelings would be different.