With MR thugs wrong thing is, MR wont help. In one of our current games, Jotunheim lost a God with MR 30+, because with many recruitable and, occasionally, freespawn paralyzers you are bound to lose at least one roll.
Dreams - well, you will probably have -1 to -2 MR thanks to dominion (I dont believe in Rlyeh without magic scale), and caster is guaranteed to have at least +3 to penetration. With halved stats and MR, your commander cant do much against the following soul slay / enslave soul (with the same +3 to penetration)
Regarding anti-Ermor, I am fighting Rlyeh right now as Bogarus, and it feels great. I lack nature (or, rather, I've got nature just recently), so my troops starve, but otherwise its just what you are looking for. The whole 'Bogarus' name means 'God's Rus'
, quite a religious country. Tainted with a blood cult, but still pious. Not peoples fault their new God has seen the worth in Blood and sent some FFA to look for virgins in several conquered provinces... Field army, simple peasants and city dwellers drafted into militia to fight for their homeland, heavy cavalry with weapons of honest sharp steel, and holy birds with voices of saints - what more can you ask for?
Since I pretty much backstabbed Ermor who was busy killing Utgard, I'm about to finish him off soon, so this story even has a happy end.