Hello,
currently, Blender’s viewport defaults to studio shading, which comes bundled with few different studio setups, but every single of them is kind of overbright, and washed out, lacking any visual contrast. Unlike matcaps, we can not add our custom studio lighting. Using matcaps is not really a solution either, since they actually override material display, not just scene lighting.
Yet another problem is that specular lighting seems to be completely unrelated to studio light setups. That results in really weird, odd looking light setups where the diffuse lighting of the scene appears completely unrelated to specular highlight shading of the model. This mismatch makes it rather unpleasant to look at.
SOLUTION:
In studio mode of solid viewport mode, add one more special studio lighting preset, which will use the lights defined in User Preferences->Lights tab for both specular and diffuse lighting. This will solve the both issues:
A. A mismatch between directions and intensities of diffuse lights and specular lights
B. Will allow users to create their custom studio lighting setup as a remedy for lack of sufficient studio lighting setups bundled with 2.8