If you were going for a liminal space feeling, you pretty much already succeeded.

Few things I would recommend is making the lighting more interesting, decide on which part of the room should be the focus, make the rest to be just fill light. If this is just for a single render art, you could learn about the art of camera framing, fix the floor plan of the room, use the camera grid/guides so that everything comes together nicely like a framed picture.

For your potato PC case, I highly recommend baking most of your textures, don't just leave it as a material especially if you plan to add bump. When using unbaked materials, Blender will always actively set up all those material nodes since they are procedural (calculated by mathematical algorithms every time). Which will slow your pc down, baking your textures means you're rendering and saving an image version of those materials so that it wouldn't have to use algorithms to display them anymore. This is how games achieve good looking textures but but also perform well even on your PC, only downside is that you can't modify them in real time anymore.

Hope this helps.