I'm hoping for all new factions! I don't mind seeing resemblances, but please give us more new design stuffs! From what I can see in the art it looks like its Eartside Guild (which doesnt so much have Ortega's, Witchling Stalkers etc.) vs something that makes me think of...Slurids!
I'm thinking we get certain factions from Alt-Earth and maybe one or two monsterous/alien factions mixed in. Doesnt mean the Earth factions need to be all Human though . The Blackpowder wars already hint at constructs, undead and magic practinioners.
I am hoping that the characters are still there, like hero leaders with special abilities and such. A bit alla Warma/Hordes, with the Casters being the bad-asses.