Yes. That is what I do. Blender provides you with the tools and
modifiers such as Extrude, Bevel, and so on. Subdividing or adding loop
cuts will help you use those to bring your imaged planes to life. Also
in edit mode you can turn on Correct Face A...
I built a world, mainly using and modifying planes in blender and with
assets I used or made and the world only used 21% Geo and 2% Obj. A lot
will mainly depend on the assets you're using.
