Absolutely, but SketchUp does not have a object and edit mode to define what should and shouldn't display. It is context based so there is an element of 'intelligence'. You are always constrained to what is exposed via the API. If you look at Vertex Tools it parks the native commands while it is operating and exposes a suite of context options that are limited to the tools function only. So having something that works globally in a SketchUp environment and considers whatever custom installs the user has would be a challenge.