Using the grease pencil looks like it could be mad fun. Might even make me go back to my abandoned dreams of learning how to draw properly.
But for this, I mostly used some of the tools. The zig-zag line was really useful for making the stairs - Which I then extruded to get the effect above. Holding shift while using that tool allowed me to make pretty straight lines without using the flat line tool - That felt much more intuitive than using Alt with a pen, too.
The lines do feel kinda wonky sometimes, though. I noticed that when I selected 2 vertices and pressed F, Blender connected the…first and last vertex from the line? Rather than using my selection. Nothing a bunch more extruding couldn’t handle, though.
I also noticed that just because you extruded from the same line, that doesn’t mean your extrudes will be part of that line? Since I couldn’t select everything with L at the end to move/scale it.