I admit I really like the design because it is rich, detailed, vivid and bright in colours. I like the combination of robotic elements with biological ones (face and hair). Considering that the image is aimed at introducing her, a static, stiff pose suits her best even though a more dynamic pose like in the case of your Spiderman fanart is a nice alternative. Robots are not easy subjects to depict so I commend you for managing to get the basic elements that give immediately the impression she's a robot. I've noticed the use of cell shading on her body, this adds further details that make the character more visually appealing.

Plus shading give the feeling the subject is more alive and realistic, even in more cartoony or simplistic styles. I've noticed though the shading is not always noticeable for example on shoulders and legs, while it's more visible on the right arm and behind the head where red hair can be seen. I don't know which digital program you use. If you use a program that has layers and modes I suggest to make a layer for shading more as clipping mask from the colour layer, but if you don't master clipping masks yet, you can always make the shading layer on top of the colour layer and then with eraser adjust and fix shaded parts that go out the border.

Anyway, shading layer, use blending mode multiply which is the best mode for shading, use a more darker grey tone and then play with opacity to reach the effect you prefer the most but make sure to make it visible unless you want to play with contrast between shaded and unshaded parts for reasons linked to what you want to achieve. A small tip for a more advanced use of multiply layer: instead of using grey colour as base for shades, use complementary colours, for example for red use green and then play with opacity level. This way you will see how the effect is even more pleasant to look at because it creates a contrast that is visually very appealing. Remember in art harmony is important but also contrast and asymmetry are very appreciated.

This video talks about the colour theory, take a look:

https://www.youtube.com/watch?v=YeI6Wqn4I78

In this video instead complementary colours are used for shading and highlights (in Krita I use overlay or screen blending mode), I think it's a nice video to start off without getting into too much more complicated concepts of shading with complementary colours:

https://www.youtube.com/watch?v=3sKGVQK-sOU

As for drawing robots I may suggest these tips I discovered myself when practicing with robotic designs:

1) sketch the wireframe to represent the robot's figure and pose (each circle represents a joint)

2) 3 dimensional shapes such as cylinders, box shapes and circles to sketch the body parts needed are always important to use when defining the overall structure

3) use lots of references for details and looks, you will learn a lot.

The only thing that I criticize is the background. The background clashes with the character because it is taken from the video game and does not give a natural atmosphere to the composition. The character seems attached to the background instead of feeling the surrounding environment. A better solution would be to draw it instead. Environments provide contexts and surround the subject, giving it the opportunity to be doing something instead of merely standing there. It's basically an interaction between a focal point and its surroundings.
Backgrounds are whatever you attach behind a character and sadly this bg is what gives me this feeling.

To learn this the first step is perspective, here an useful resource: http://drawabox.com/

but this video is useful too when it comes to backgrounds tips: https://www.youtube.com/watch?v=tVynETvms-o

Another advice: the background should complement the characters, never make it stand more than others or compete with the characters otherwise it feels weird and gives off vibes.

Besides these advice I gave you, the design is nice with vivid colours, this is why I gave 3.5
Keep practicing, having fun and learning!

The Mimi Sentry! :> Nice!