I don’t find that my workflow significantly increases file size. It may do so because components have a wee bit more overhead than groups usually do but for me, the benefits of using only components far outweigh any minor file size increase that might cause.
My projects don’t cover the kind of square feet a house would but they are typically highly detailed anyway.
As for whether or not my workflow would be a benefit to you, I guess I’d suggest you try it.
One way you might look at your modeling is to think of it as a sort of finite bank account. Every edge, face, or texture you add costs file size. Where do you need to “spend” your file size? Does the fridge or dishwasher you put in the kitchen need to be anything more than a door? Does the sink really need a strainer in the drain? Does the fireplace need a grate and logs or could you just use an image as a texture? You probably see where that is going. Just don’t add things that really don’t have value in the model for the way it’ll be used.
What do you think?