Direct hit should be biggest dps increase, but that not affect for healing skills. Crit is useful for adlo, but using adlo is pretty rare now since mana control not allow us use it much and crit is pretty poor stat until you can stack like 3k for it. Determination would probably be the best choice for both healing and damaging perspective I think. Piety would in theory allow scholar spam more adlo and in that way have better dps uptime. spell speed, well I m not fan of it.

It also depends how much you have to heal and dps. Lets say if you can dps over 80% time in savage, I would meld everything for direct hit.