Scapple is a single corkboard.

You should not forget that Scapple is the little sister of sth big: Scrivener.

You drag your maps to Scrivener, you would have a draft to go. Indeed, if your project is smaller in size, you can do all the drafting in Scapple; and finish it up in Scrivener. They work together really nicely.

Curio is also great. I had experience with it a long time ago: never checked it lately. But, Curiota, the little sister, incredibly effective for jotting small ideas as they pop up in your head.