I would like to request a feature - trim intersecting surfaces. You would draw 2 intersecting flat surfaces, select this tool, then click on both surfaces and the tool would trim the surfaces at the intersection line.
A more challenging feature would be to do the same with non - intersecting surfaces. I’m not sure how you could go about extending the surfaces though.
Also, trim tool could be made to trim 3 surfaces at once. You would select 3 surfaces and use this tool, and it would create a corner and 3 edges.
I’ve found one plug-in that does basically this, but it is on a third-party website.( not on extension warehouse). I don’t trust the site to try it, plus its not free. The plug-in can extend/trim faces according to videos.
With the example Anssi gave and the one I showed, making those faces into solids, I don’t think the soild tools would easily give the desired result, unless there’s some trick that I don’t know.
I spend a significant amount of time in SketchUp drawing buildings. This issue comes up when drawing roofs. The intersections between different roof planes can be quite complex. Roofs end up taking quite a bit of time to clean up. Sometimes I get misaligned faces or small gaps between different faces.
I think I understand what you are seeking and can see how some automation might help. That said, I’d suggest you make sure you are leveraging tools like rotated rectangle and inferencing to their fullest.
I’ve found these to quite powerful for roof work.