You're abolutely right that the classless structure is a big factor in why people play EVE. There was a lot I wish I could have gotten into the article but for the sake of keeping it at the usual length, I stuck to the parts that other MMOs could easily adapt for themselves. I went into detail on the factor of a player-run economy in my article on the server model and explained how a player-run economy wouldn't really work without the server model EVE uses.