Why exactly hasn't OOO upped the "exploration" feeling within this game?

I feel that one of the strengths of this game is the feeling that there's always a great unknown, as if there's something great, that's just WAITING for you to see it. For instance, that first time you see the core. You just battled all the way down for the first time, taking down the great Lord Vanaduke, fighting with all you've got, and you make it down. You've finally done it!

You walk forward, the camera pans, and you see this gigantic.... thing. It's humongous, and you've never seen anything quite like it before. What is it? Why does it exist? How do you make it in there? What IS in there?

You see, I'm not quite sure if everyone felt as I did the first time I saw the core, but it was mind boggling. I felt as if there was so much I still had to see, and so much that was still unexplored. I LOVE feeling like that, as if there's something new to see every time. The problem is that feeling of "the unknown" can only persist if there's still things that are, yknow, unknown, and the world as a whole doesn't necessarily feel limited.

If it wasn't obvious where I was going with this, I'm saying that the game, as a whole, gets far too predictable for its own good.

So back to my question, why hasn't OOO really upped the feeling of exploration in Spiral Knights?