I think maybe having more common non-mobile traps and hazards would improve the feel of the game somewhat.
Things like randomly placed bear traps, flame jets on a timer, exploding plants, or maybe even sticky goo on the floor.
Psychologically it seems like "traps" feel more like part of the environment and so make the environment feel more diverse just by being there. They wouldn't have to be particularly life-threatening, but having them there might improve the "feel" of the game. They also may bridge the gap between "enemies" and the "terrain" so they don't feel as separate as they do now.
I notice that lot of platformers have almost as many minor "traps" as they do mobile "enemies", sometimes more. It's enough that their rarity in AVWW feels a bit odd at times.