Scale selective loft curves.

I've lofted a series of rectangles which follow a curve to make a simple building form. I want to vertically scale selective parts of the building to allow for desired views, however I want to scale these sections progressively so that the building retains a flowing form.

So far I am able to split the data of the sections I want to change the scale of, however I don't know how to scale them in a way which is not abrupt.

Is there anyone who is able to point me in the right direction for this? I've also attached an image of the workspace which hopefully makes what I'm talking about clearer.