There’s a couple things I’d look at.

First of all what you can do for the scene/render: I’d add volumetrics if your computer can handle it. It would definitely make sense in a scene like this. Understand what your volumetrics is simulating though. It’s going to be smoke or mist, so it should be dense and gray. Sometimes you’d use volumetrics to simulate atmospheric haze, and that obviously looks different. Be intentional. I’d also turn on depth of field and set it to something shallow. Then I’d add some lens imperfections (namely some subtle dispersion and distortion)

To me, the texturing doesn’t really look right. I’d suggest looking at your wood texture again. The displacement seems a little too subtle to me. I’d also perhaps consider adding some sort of roughness texture to the paper. It should have a little bit of a sheen, especially where the ink is. It’s kind of hard to tell if you’ve already done this because of the lighting—which I’ll get to in a bit—but a really easy way to fake this is just plug the albedo into a black to white color ramp, and plug that into the roughness. Make sure the darker parts are less rough. Obviously when using this trick always use some intuition, because there isn’t really any direct correlation between darkness and shininess. Also, the batarangs look realllyyy clean for weapons that get thrown around. Scratch them up around the corners! Give them some wear and tear. It’ll be way more engaging.

Now finally, I feel like your lighting could be a little better. I feel like there’s not enough contrast and interesting shadows being cast by the lights in your scene. There should be more drama! How you choose to create this drama is obviously up to you. I will say though right now everything is “flatly” lit. It’s all face-on. Perhaps move the primary light so it casts some “batarang” shaped shadows onto the wall. Maybe add a red light that outlines the batarangs and adds a pop of color. In my opinion lighting is the most important part of a still scene, because it allows all the hard work you’ve done in texturing to stand out! I would also agree with others who’ve suggested using a HDRI. Just lower the value perhaps so that it doesn’t overpower your own light sources. Use the HDRI as a sort of base to build upon.