The modeling here is very good. I won't comment on the design, as I am an architect, and understand how design styles are truly subjective. Some things to consider if you redo this rendering would be to let your people, other objects, etc.. cast shadows, aand to figure out what is sausing your lines to become wavy (did you accdientally inproprotinately resize this image?).

You are right, the shadows are missing because there is no light source, just gi. And the lines are distorted from resize. I looked at your images and i'm very impressed. Beautiful work, your renders are very, very realistic. Congratulations!

Aye, I don't know why you would resize the image? Also, I think it would be a better image without the photo-people, they really detract from the realism. But it's a great house model!