Since we are all new players, I would think using mods is a bad idea.
Why are the reasons for not playing with R'lyeah obvious? As a new player, they're certainly not obvious to me. The dominion thing? Is it that unbalanced?
If we are allowing Ermor, I wouldn't mind giving them a go instead of Tien Chi. I have played with them in EA and MA in single player games and like them thematically. Since I don't really know what I am doing, I suspect I won't be too difficult to defeat :-)
A good mod is that Worthy Heroes mod, it makes the random heroes you can get much, much better. As it is some nations get almost completely useless ones. And almost every MP game uses it so it wouldn't really be much adjustment for new players.
Ossa: you have to chose a nation you can not go random
Gowb: That would be a good mod to use so we will probably use it
Goodchild: Your in
ghostwes: the reason why R'lyeh would be a bad idea is that they are the hardest to actually fight with insanity and all that, and yes you can use Ermor