In broad general terms. RMAH for softcore, DPS items sell for a lot more than survivability. Hardcore mode its the opposite. So some crazy max main stat, +crit, +crit damage, +socket, +% damage to elites with a splash of other things will sell for big bucks, but prolly wont on Hard Core where max vit, +life%, +resist all, +armor, +control reduction will.

Weird things also like +Gold find with gold pickup sell really well.