Currently the perspective of the 3D models only can be changed by rotating the *camera* around the model by applying Behavior3D.ChangePerspective. This has the disadvantage that when examining the model in space one will invariably end up in dark and shadowy areas of it, since the light sources don't rotate along, which is less than ideal.

The more optimal behavior would be to rotate the *model* instead, which always keeps the light sources at the same angle to camera and model, and thus provides consistent illumination. Therefore the implementation of an additional behavior enumeration e.g. called Behavior3D.RotateModel could vastly improve the user experience.

You are right - I actually did have some static lights applied. I added them because the Chart3D model gets over-proportionally dark when viewing a surface from less than a 45°C angle, but still fully in light direction. Is there a way to ease this effect a bit, towards a less high-contrast image result?

I've found that the addition of an AmbientLight does the trick to ease the contrasts. Following light combination currently works pretty well for my stacked 3D chart with cylinders, maybe it also helps someone else (vb.net):

with myChart3D
.Lights.Clear()
.StaticLights.Clear()
.StaticLights.Add(New AmbientLight(Color.FromRgb(110, 110, 110)))

Dim light = New DirectionalLight()
With light
.Color = Color.FromRgb(155, 155, 155)
.Direction = New Vector3D(-1, -1, -2)
End With
.StaticLights.Add(light)
end with