Tips or critiques appreciates

[Servyl]

So I just drew up yhis quick eye, nothing too special, but I was looking to put more emphasis on the shading and highlights this time. I know it definitely needs some tweaking up, I'm still a newbie by all means when it comes to shading, highlights, contrast etc. So does anyone have any suggestions to generally just really make this pop in color? Whatever would make it more appealing to the eye

 

[BSporn]

It's really hard to give you tips for the eye in isolation without knowing what the rest of the picture is?

Or is it just the eye.
If it's just the eye you're going to want to work on framing and contrast. White eye + white background means it's all going to blend together. Things stand out with contrast so pick a dark background colour on the opposite spectrum to your eye like a maroon or a purple.
There's also no real background elements that lead your eye towards the eye, some abstract leading lines, in shapes directing the view towards the eye would help.

 

[BSporn]

If it's just the shading you are looking at improving you're not really shading it as a sphere.

Remember the eye is a 3d sphere in space. The shadow at the top is being cast by the eye lashes. So should conform to the shape of the eye lashes you'd also be seeing a smaller shadow cast at the bottom of the eye by the lower lid. As its a shadow it would also be affecting the Iris of the eye. The specular highlight (white dot) would not fall in the shadow as its the most concentrated part of the light reflections.
It can also help to remember that the Iris and pupil are actually a flat plane inset in the sphere with a clear bit of sphere over the top of them. They're not wrapped around the outside. So try and place the pupil specifically inset in a bit to help it give the feeling of depth.