This is the much needed tool for event layout makers. When you work on angular drawing say putting stalls on 30 deg angle and you going to select them but tradition selection rectangle selects everything comes at its corners so if we have 3 point selection rectangle then we can draw a line at 30 deg angle and select only those stalls.
same with when we work on circular drawing like stadium seating then its a real pain to select a row of chairs which require circular selection tool.
CorelDRAW and Corel DESIGNER provide a freehand selection lasso that can be used to draw a selection in any shape, which should cover the use cases you've explained in the feature suggestion for 3-point rectangle or circle selection shape.
Corel DESIGNER also provides projected selection options. As you can see in the below screenshot, you can draw a projected rectangular selection with the default Pick tool with a projected view plane active (e.g., right isometric view selected in the Projected Axes docker).