The hardcore players are going to get their XP as fast as they can, and they're going to find creative ways to do it, hence the grinding groups that I see advertised. But for solo and casual players, especially groups of two, it would be nice to get more XP, and more than 2 or 3 gold, from killings mobs. The quests seem to give you good XP, gold, and loot, but the mobs seem more of a punishment. They seem to be an obstacle on your way to a quest or to finishing a quest, and since you don't get much gold or XP from them, one tends to avoid them as much as possible in order to finish a quest. Also, if you're trying to keep in-sync with your partner for quests, it would be nice to kill mobs for something to do, until you can quest with your partner again. So it would be much more rewarding to kill mobs if we got something substantial from them rather than just be a way to dull your weapon and break your armor.
"Perhaps his egg spent too much time in the shade before his hatching." -Wareem-