Two or three. Two, because you've already fleshed it out a bit, and what's there sounds /awesome/. I love magic, intrigue, and all that fun stuff. The prospect of essentially 'stealing' a Seeding offers a really cool source of tension and striving, and the Dark Seeders make for interesting bad guys who could easily hide in plain sight. Good, simple but eminently playable setup.
Three, provided it turned into a colonization game. I've /always/ wanted to play a really good SF colonizing-a-hostile/strange-planet game, and that sounds like it could fit the bill. Without it being fleshed out a bit more, it's hard to say which my vote would go to definitively, but either of those two would be a hell of a lot of fun, I'm sure.