I think that adding preselection highlight for subobject elements will be very helpful. This way you will know which vertex/edge/polygon you'll select when your cursor hovers over them. There's already preselection highlight for objects in Max introduced a couple of releases ago and it proved very useful when picking stuff in the scene. Adding this feature for subobject elements too will be equally as useful.
A lot of 3d software already have this feature - Maya, Houdini, Cinema 4D, Modo, etc. It seems that only Max and a couple of others are still behind in this regard.
Here's an example of how it might look or work: