Hey! You can most definitely create floor plans and elevations entirely in 2D using SketchUp. I know this because I teach online SketchUp courses to Interior Designers and students on how to do this. I’ve actually taught Degree students who were using (and struggling with) AutoCAD and I advised them to make the switch to SketchUp because it’s just so much easier and quicker.
It’s actually very straightforward to create traditional 2D symbols like doors and windows. A lot easier than creating 3D geometry. I would recommend the Camera view of TOP, with parallel projection and the Style of Hidden Line. You should be able to apply all of your textures in SketchUp, including dashed lines if necessary and then export to LayOut where you can apply different line weights, annotations, dimensions, text labels and a title block.
Let me know if you have any questions! You should check out my blog post where I put AutoCAD and SketchUp head-to-head for the same 2D floor plan :).
Anita