The R'lyeh one is scary! I don't know what, exactly, it is, but it suits them frighteningly well. Jotunheim and Vanheim also have great banners.
Ulm looks a bit bland, and the crescent seem (to me) to be slightly different than the one in the higher-resolution Black Forest shields... But it might as well be that you took it from there, and I'm more accustomed to the low-res shields of Dom:PPP era.
I didn't quess it was C'tis from the banner, and Man's and Pangaea's flags could fit either one. Personally, I think the Harp would suit the nation of Bards better.
And I think Pangaea could well have a human skull/head on top of its banner. The Panii lead the nation, after all.
I always thought of Broken Empire Ermor as being more purple than black, but the current one fits the undead themes just fine and they're probably what's played more often.
The Ulm/Vanheim/Arcos/Caelum/C'tis etc banners with the uneven bottom could use some shadowing or something in the bottom, currently they look like too static and clean. Mictlan one is just fine, and the Pythium banner is also better than the others.
I think I commented most of them, but this doens't mean that I only like few ones! These are [img]/threads/images/Graemlins/icon44.gif[/img] great, and I think these kinds of flags fit the game
much better than the emblems Jurri used.
As your mod has already been compared with Jurri's quite similar one, maybe you'd like to update the nations' GUIs? If you're going to do something, check out the Marignon GUI Jurri used. It's awesome in how it fits the game, and how the game uses it. Remember to also check the Escape menu. It's just unbelievable how well the sun gets placed.