Vertex Parent on Curve Points Should Use Curve Tangent and Tilt to Rotate Child Objects

Currently to make a child object parented to a curve point rotate as the curve moves, you need to create a mesh, such as a cylinder and make it follow the curve using the curve modifier. Once you have done this, you can parent the child object to three vertices on the mesh and the child will rotate with the vertices. If you only have one vertex, there is not enough information to determine how the child should be rotated, so it will not rotate, and only move when the curve point it is parented to is moved.

This shows an object moving with a curve point:

This shows an object moving with vertices of an object with a curve modifier:

However, unlike a vertex on a regular mesh, a curve point has not only a position, but also a tangent and a tilt. This means that Blender should be able to calculate a full transformation matrix for the curve point and use that to both move and rotate an object parented to it. This would make setting up objects parented to curves easier, and it would also remove reliance on the vertices of objects following the curve, which could change and the parent setup become invalid. Note that even though the setup in the second picture was simple, it was far more time-consuming than the first, and the result is still not really correct. A better result could probably be achieved by using the array modifier to fit a smaller object to curve length, but in any case, it's not ideal, and it would be great to be able to rely on only the curve, using the bevel settings to get a visible curve mesh that can be controlled more easily.