Stat weights are nearly irrelevant considering how small a difference you can actually make to your healing through secondaries. Even if you could meld solely for one stat (you can't because of stat caps) and even if you had several gear choices (you don't) weapon damage and mind make up far more of your actual throughput making them the only "real" stats in the game aside from accuracy (assuming your doing content at a level to need to dps and not playing casually). So with that in mind:
accuracy - until you have enough. This is the only stat that has a meaningful impact on what you can accomplish during a fight and substantially impact the throughput you have, though it is dps.
crit - shields more often is a better real world result than slightly stronger shields regardless of stat weight which is why you prioritize this over det.
det - better than SS since you get a sort of double dip usage with the crit shields and you have so few HoT to make stronger via ss.
ss - more or less useless because you can't put together enough to provide a meaningful benefit in scripted fights with predictable damage.
pie - if your gear is at level for the content you are doing then you should have enough, even dpsing. If you are running out of mana, look for people making mistakes causing extra healing, and look at your own choices of heals during a fight before adding piety.