For a few years now, it frustrates me that the MotionPlanning display property is the only way to change the active planning group.
The user has to expand the properties of the display, expand the properties of "Planning Request" only to change the planning group property.

With multi-arm setups or setups that model the gripper as a planning group, this is very annoying.

I propose to add a drop-down menu to the "Query" box in the "Planning" tab of the panel right above "Select Start State:".
This should always have the value of the mentioned property, exposing it for easy access.

This issue requires previous insight into RViz programming to finish it in one day.