I think "Heaven's Bless" is better than "Shiel of Fire" in these ways:
(1) "HB" can make roles resurrect;
(2) "HB" can be used on roles even when they are full HP, but "SF" is not;
(3) When "HB" add to certain role, it will restore continuously. But "SF" just restore when casting.
Shield of fire used to be healing overtime while heaven of bless was instant, to be honest i never understood why it got swaped rlly, when shield of fire became instant it became death for me too, but if shield of fire return to be overtime i would use it over heaven of bless since the extra armour can make a long way.