Great chart Soup
However, I think a lot of these goods are stuff that shouldnt really be sold at all. All tools and crafted things, (except what takes some time to make, like cake) should be sold just as the materials. Like all armor, diamonds tools, iron tools (you dont have stone tools on the list for instance
) You should also divide it into the 2 categories: "Often Traded" and "Some Whacko Will buy this once a month".
All the major materials: logs, diamonds, iron bars, wool, snow, glass, coal, dirt, sand, netherrack, smoothstone and cobble should atleast be in the often traded one. (perhaps I forgot some)
Nearly everything else should be in the other one, where some of those are more often traded than others but still. Wheat for instance sells for crap. Also crafted things like stairs and halfblocks etc are just annoying to be trading in at all.
Then all the things in Often Traded is like the main Stock market where the prices of the different things greatly influence the economy on the server.
One more thing, I think some of the prices you have set have been based on the prices at chest shops at spawn with rediculously retarded prices. Like smoothstone and netherrack.
Just a note to everyone: The prices at the shops at spawn are in no way representative for the prices currently in the server. Most of the prices are extremely high for selling due to their location, and the rent the shopowners pay to keep the shops there.