Kill the Dwarves, keep the Barbarians, add neutral creatures, and a creative faction that no one has ever seen in any game, something that would be incredibly engaging with its unique abilities (insane combat tactics, crazy buildings, etc.), and the game would be wildly popular. Hmm... a faction of madmen would fit perfectly. And their global goals would be so outrageous that it would make everyone burst out laughing %))). In short, a super-fun and super-crazy faction!!!
P.S.
I, for example, don't acknowledge the existence of Dwarves as a faction at all!