First few hours in and I was amazed, but that feeling quickly faded exponentially. I spent a lot of time in the depths despite the lack of variety, just because the concept was appealing to me. I kept hoping to stumble on something new even though I knew there likely wasn't anything new to discover. So, I'm left pretty sour on it now.
The caves on the other hand, are the best part of the game. Focused and purposeful design, with a surprising amount of variety. Different elements, gimmicks and scenarios, and even wildly different layouts. There's very few that don't have something unique going on.
I would have rather the depths been an extension of caves, like a hub area connecting to various cave systems. Larger chambers but with intentional design rather than just inverting the entire existing map and slapping random bits in.