I think that new stories should cost more, and maybe you could get gems from getting your drafts chosen. That way there aren't so many stories sitting around and not getting actually written beyond the first chapter.
You do get points from having your draft chosen, which I believe also translate into gems.
About having new stories cost more, this was a thing (was 20 gems), but the price was lowered. Before the introduction of having stories cost gems, there were already many, many stories, so reraising the price might not be a good idea.
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