3) is exactly what I'd love to see. It doesn't have to be our Europe specifically, but our "Old World." I'd love to see an exploration age at some point in this roleplay, so 3 is exactly what I want. And we shouldn't know much about the New World when it finally appears on the map. We might have old documents that hint at its presence, or certain folks might actively go there (English fishermen were actually fishing off the coast of North America for a while before it was colonized), but we should effectively know jack all about what's over there.

If I had to choose between 1 and 2, I'd choose 1. But again, I don't want to lock our minds around the idea of "Europe." What if someone wants to play a China-like empire? Or something reminiscent of ancient Babylon? Heck, what if someone makes something that doesn't quite fit into something from our world at all? Etc.

(I'm debating between what cultures to draw inspiration from and what fantasy species I want in my empire.)