Progress continues! I've gone through and edited nearly 60 screens, improving visuals and ambiance. In addition, I've added several new screens and improved some tilesets. I've tried to reduce as much backtracking as possible but there are still some secrets and things that will require backtracking.
Here are a couple new screenshots for you guys.
I've also updated the initial post to reflect some changes to the level overall. One major change is that there is now only one ending. I feel this better suits the level.