Update 2
I know it's been a while since I updated this Topic, but in that time I began playing around with the fortress structure underneath the main spire. And... I wasn't satisfied. So I decided to scrap it completely and restart it.
This time around, I started with the tower again. Looking at reference images, I noticed that I got the shape and colors of the window towers completely wrong, so I fixed that here. And because, in the Legends of Chima show, this section of Eagle Spire houses the library, I tried to replicate that here (it was originally going to be an office for Ewald). The size is also doubled: whereas the first draft of the tower was roughly 8 studs by 8 studs, this one is 16 studs by 16 studs.