Many Rhino commands make surfaces. Most of these commands have windows which allow the user to adjust the new surface and look at it from different angles before the user accepts its final shape. The user looks at the new surface in the perspective view, holds the right mouse button, and rotates the view. Most of the time the surface disappears from the viewport because viewport target location is far away from the surface. This problem has easy fix - set the viewport target location before making the new surface.
The fix is easy, but it is a waste of time and a nuisance. In my opinion, Rhino should automatically adjust the viewport target location when the new surface is being made. The target location should be the same as the center of the bounding box of the new surface. This new is feature is easy to make and it would be great time saver for Rhino users.
Viewport Properties panel > Target should have an option that automatically picks up center of bounding box of selected object.