I like the overall design change. Dark mode is nice and scrolling through the Sandcastles looks great.
One of my main use-cases of Sandcastle is a quick reference to “what is possible”.
For example:
- the Geometry and Appearances for geometry options
- the three different Voxel applications: Voxel Picking, 3D Tiles Voxels, Voxels
Wanting to check out multiple examples in quick succession might be annoying if the Gallery is hidden by the code window. Others may disagree with this use-case.
My other main use-cases are noted by David above:
- looking for a reference of how to build something
- get a prototype running
- communicate a Cesium feature/issue to the team or on the forums.