Akaza second highest.

If Akaza ate women the same way he eats men, could he surpass Douma over time?

Is that rumor true that Muzan forbade Kokushibo from eating humans to "prevent him from surpassing him" and thus reveal himself?

Why does Kokushibo have the rank of first superior? It's a stupid question but why? In the sense of going completely deep, not just something superficial like "oh I had a lot of inspiration and greed."