Joonie73-
The NGs are not supposed to be uberunits by themselves - their big problem is the low attack so high defense units can stall them. But like Zen said - with a strength that high they just destroy HI that have lower defense values and depend on ~18-20 protection to save them. And the chill effect means that if a high defense unit can't hurt the NG quickly, they will likely get frozen which reduces defense, so now they will get hit - hard.
But the bless effects can correct their weakness, and Nature is my fav there for them too. The +3 beserk is probably better than the +4 armor from earth or +4 attack from fire - they get +3 armor, +3 attack (which means now they can hit most high defense units every couple of rounds!), and +3 strength and no chance of fleeing. Their defense is only fair to start off with and they are so big they will get ganged up on, so the -3 defense is little loss IMHO. And 10 HP+ regen and high armor means that without high damage units around, they will win against most opponents with little loss.
Keir-
For a fun dual bless choice, have you tried a Baphomant with Marignon yet? Cheapest dual 9 magic pretender there is (I think - only 468 points), and twisted fate flaming attack flagellants are a whole lotta fun
It's good being the Astral King, too! Too bad no one else gets to choose him as a pretender...