Hmm.. there's actually quite a bit you can improve on here. I'll make a list and show ya an example :]
-The objects have no outlines at all, any time you sprite anything you should make sure it has an outline to make it stand out more. Without outlines everything looks all mushed together.
-Your perspective is off. Since RMXP games are usually top down you need to show a bit of the top of the monitor. Even if it's a flat screen(which I believe this is) there's still a top to it. The top should also be a much lighter color than the front. Which brings me to my next point.
-Your palettes. For one they lack contrast, two there's too many shades, and 3 they're flat. This is an easy one, just pick less colors which are farther apart. To get rid of the flatness just tint your shadows violet and your highlights yellow.
-Lastly is just shading errors. Your shading actually wasn't too bad, the monitor should cast a small shadow on the base and you'd have to adjust the front a bit after you add on the top but that's about it. Check out my edit to see what I mean: