In my experience, the shooting environment is more important than the camera gear. Especially these days when high mega-pixel cameras are the norm on everyone's smartphone. The biggest impediment today to getting a great photographic image is not being in control of the lighting, and perhaps more importantly, not knowing what the best lighting environment ought to be to begin with. Photography is referred to as "the art of painting with light" for a reason.
So before you rush out to buy hundreds of $$$ of new camera equipment, first learn how to properly light your subject (i.e., your keyboard), and then figure out how to control your shooting environment to give you the lighting you need. You will probably find that your money is better spent on lights, reflectors, and diffusion materials rather than a new camera, lenses, and filters.
And it wouldn't hurt to master the concept of white balance too...