Looks good to me!
At times the highlights would just "outline" the shape along the edge to create details where there are none.
At times the highlights would hit the areas that pick up the "light" to create contrast.
At times a dry-brush highlight just creating contrast by amplifying the sculptor's skill and model detail.
If the models has the contrast, and the detail, and reads well from afar, then the highlighting has done its job in my opinion.
Then there are just the levels of skill in which the highlights are applied in, that only matter when miniature is held up for closer look.
From experience, the skin is most difficult to highlight because it never has that extra contrast and from far away all looks a bit too uniformed.
Also, I found that there are some miniatures that is a joy and pleasure to highlight and others is a chore and for others it doesn't have much of a significant impact.
It is up to the sculptor to not only make awesome miniature, but build it in a way that makes sense for painting.
To take highlighting to the next step, apply an extra highlight on top of the current one, to have an effect of a rough two-color "gradient" :
1 - The light-blue that is already there
2 - And a lighter version of that blue in areas that pick up the light the most
The model will have a rough gradient from, washed dark -to- base blue, -to- light-blue light, -to- even lighter-blue highlight
Hope that helps, and or makes sense