One of the features I have always missed in modelling programs is the ability to “tag” vericies. I’d go a step further though. I’d really like to see the ability to set a number of tags or attributes to a vertex. This would allow scripts to really go to town on mesh management.
Face (human) mods. If facial parts eyelids, noses, lips, etc. could be constructed separately and then have their verticies marked as eyelid verts, but also the outer edge verts would be additionally marked as border vericies (the ones that need to be connected to the rest of the face) and one of those be marked with an alignment mark. It would be easy (much easier) for scripts to assemble custom faces and “sew” the pieces together.
Also transforms would be very easy by script. A script could easily reposition eyelid verticies (from the left eye) according to a repositioned left eye ball.
A fall back would be to simply give each vertex a PERSISTAN unique id (not vertex index), so that this info could be held outside the blend file.
If I too am missing the better way, I’d love to hear what it is.