I won't be able to give you a conclusive answer but as we are an architecture/interior architecture/landscape design company and use OG4pro I guess there is something I could say about what you want to achieve.
As long as you can clearly communicate what you want for your new home any medium will do fine. A scribble on a paper tissue is fine, so is OG4. Most important thing you should think of is "how" do you want your new home to work for you, what style, what atmosphere and so forth.
I would recommend to cut out photos from magazines which describe what you have in mind. With those and some idea about the dimensions of your room(s) the architect, if any good, shoudl be able to translate your wishes into something that works.
In OG4 use simply the rectangles and draw walls, door openings and location of the windows. No need to go about fiddling with insulation, different layers of walls (construction) and whatever. What you might want to consider is the location of electricity (outlets) lighting, network connections (if not wireless) and other elements which make life easier or more of a hassle. Sounds a bit weird but the location of these could spare you a trip to the DIY store for extension cords...
However, you should have a fairly good idea of the spaces before you could do the above, consider it a second or even third phase. Hope this makes sense.
OG4 works but keep it simple as there's no need to go into details.