Creating more depth in a scene

Hi all, Thank you for reading this

Background: I currently have a scene of a character (monkey) that looks at 4 separate objects on a platform. It does this using eye movement only, or eye and head movement. These movements are rendered as animations but I have only provided one rendered frame here of the eye & head movement.

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Critique needed/Issue: The rendered results/scene at the moment does not have much depth, and therefore it is difficult to make out what the monkey is looking at. I’m looking at any criticism and suggestions to improve this aspect of the scene and/or character.

Current steps taken to resolve this issue (Any suggestions as to how to best achieve the goals below is appreciated)

I’m currently working on constructing another eye ball with better corneal reflection (with BSDF shaders etc) that will provide some depth cues. Working on changing the lighting of the scene to improve depth. Changing the focal length of the camera

Any suggestions is very much appreciated,

best, B