It is hard to say but I usually go with maxing DPS which means maxing dex and str with the rest in con. Previously str didn't help dps enough to warrant maxing (IMO) but now I think it does, especially since it helps blocking.
I like the added resists from con better than the HP gain. Damage mitigation is better than overall HPs since it means less damage to heal, thus a healers mana pool won't get taxed as easily.
It is both great and frustrating that I feel I should be maxing all three
