I think that the more things that a player has to actually do in game, be it killing a different mob, grouping to kill a bigger mob, crafting, mining, questing etc the less of the crowding around one or two mob types hitting the agro button, then 5 to 15 seconds later hitting the loot button.
I would think that improving the variety of mobs and number of spawns, and either upping loot drops or the values of the items that are dropped, OR lowering the cost on training up, should be a higher priority than thieving or stealth.
Maybe having a larger world would help too, right now most of the game feels like playing in a shoe box.