[Evilhomer]

Fire is not at all clearly the best bless.... Mostly it depends on what nation and what blessable unit you have available - if you need to make generalisations i would probably pick water as the number 1 bless. The weakest blesses are probably death, air and blood.

Astral 9 doesn't need help either, for certain units the mr is very good (demonic/undead) -and its pretty cheep with an oracle chassis and twist fate is added gravy on top.

For some reason you list earth as one of the weakest blesses when it's clearly one of the best - 4 more protection is not bad at all and the reinvig will help alot on those heavy armor blessables you probably are using (aswell as helping sacred mages).