Critique Request on Concept art for a remake of Abadox, Part 2 Thread

So, my old thread on this was closed, I guess because it didn't get any posts for awhile, so I'm continuing it in this one. I hope that's okay.

Here's a link to the original thread: Moddb.com

The short version is that I'm mostly an artist and a fan of an NES game called Abadox, which I'd like to remake as a PS2-era survival horror game. See the original post to see the first few drawings I did, or feel free to ask questions if you'd like to know more.

Anyway, I took a bit of a hiatus, but here's more concept art.

An attempt at a level that's basically the inside of a mouth. I basically drew the inside of a cave based on a photo, then colored it based on photos of the inside of a mouth. I think the end result is too plain to be a level, but it was a fun experiment.

The monster's nerve center. Again, I used a photo of the inside of a cave as reference, but based the details on the level of the original game. Fairly happy with how it turned out, but it took FOREVER!

The “Shark Guardian”--I'm really happy with how this one turned out.

As always, I'd appreciate any feedback!