HOL Genre 2.0 - Dimension
 

The dimension field fundamentally differentiates between 2D and 3D games but it also separates 3D at a certain level of granularity.

One important point is that I didn't consider fixed plane games like Spindizzy Worlds as 3D but rather 2D graphics at an angle. There might be some difficulty in the distinction here but generally 3D is used for free-moving vector or other graphics.

Dimension Types
 

2D
3D
3D (Dots)
3D (Filled)
3D (Gouraud Shading)
3D (Rendered)
3D (Sprites)
3D (Texturemap)
3D (Voxel)
3D (Wireframe)
Hybrid 2D Sprite & 3D
None