Is the Nature court one very large court? Are there smaller, more specific sub-courts within it? Or is Nature less of a formal court and more of an alignment, like Seelie and Unseelie?

Almost all things humans are calling courts, like Seelie, Unseelie, Nature and others, are really alignments.   This being said, there are courts based on them.  But there isn’t one single head, we don’t have a single top king or queen or ruler or anything.  Even the largest courts don’t have any monopoly on power.  

Long story short, there’s no one ruler of any court.  Nature is often less formal, but we can be, when we need to be.   But if we had to be, we wouldn’t, you see?