1. The site loads quickly! [light, unobtrusive design, nothing лишнее]
2. No advertising (I understand that advertising drives trade, but we're not trading anything, yet...)
3. The site is constantly updated, i.e., it's extremely informative, with as much information as possible on the main page, but not overloaded, and of course, everything should be conveniently and easily found, at least a good search script is needed....