And, yes, sometimes it is still best to start with pen on paper. Fountain pen if possible. Ideally using South Sea Blue ink, but black can be nice as well.
As one professor of mine said, often, Circles are expensive. He know that, he too likes to use circles, curves, swoopies. Call them what you like, they can be well worth the investment. That investment than creating scenery is on thing, but when building swoopy architecture, that investment takes on a whole new meaning.
Check out the Marilyn Monroe Towers.