Candyman & Pypebros:
I opted to adjust the brightness and shading a little bit rather than add a detail like a railing; that adds more of a divide in depth than i want to have, as ideally the stairs should be only directly in front of the pillars behind it. I may still make the pillars darker but that's something I'm going to worry about when I've made some more progress. Similarly, I might edit the bottom part entirely to make some stronger shadows under the second floor and behind the two rows of pillars.
Ryumaru: Long time no see, haha. I've rebooted it a couple times since then and I've been working on getting my art abilities where I want them to be first. By mechanical, do you refer to tiling repetition, or do you mean the nature of the shapes?
In any case, I've got an update here.

I might be making the part above the "hole" something else entirely. Maybe something framed by columns with a sort of enclave in between them.