Dark Tower

Yo folks. You may recognize me from my castle town I uploaded on this forums earlier. Also, make sure to check out my Youtube channel Revolvee
Anyways, this is a tower I've built on the same world as the castle town and my mountain town. It's not at all done yet, but I'd greatly appreciate some feedback, on all parts.
The thing about this tower is that I wanted to base it on the terrain around it, rather than flatening out the ground first. And also, this is NOT an attempt to make a replica of Isengard. The top of the tower was inspired by it, but really, if I wanted to make Isengard, I would've made Isengard. This, is a tower by Revolve.

I need some great feedback, especielly on the details of the tower, what I can add/remove, the "courtyard" and the interior. Cheers