Provide something analogous to IDisplayFeedback2 in Pro SDK

[KirkKuykendall1]

By implementing IDisplayFeedback2,  ArcObjects programmers have been able to deploy applications with great usability: as the user draws a sketch, graphics on the screen dynamically refreshing as the mouse moves.

For example, see the ToolAndControl Arcobjects Community Sample.

From what I can tell, the ArcGIS Pro SDK has no equivalent, making it difficult for programmers porting legacy ArcObjects applications to Pro.  (If I'm wrong, then maybe what's needed is simply more documentation.)

This might also address a requirement for the ability to change the default symbol that is displayed, mentioned in this Community Question.