Well, the skull quests are really interesting...
So far I gained 1 rare soul and 15 precious fragments on main acct, while my alt already cashed in 3 skill shards, a rare soul, a warrior soul and 20 fragments.

I'll be tracking the rewards gained for a couple weeks as I don't want to jump to conclusions whether the skull quests are good or not, especially with the huge discrepancy between my two accounts' rewards