My idea was just to keep the user experiences consistent across the dashboard widgets usage. But even if property cant be used the main concept still stays valid.
as I said - it "should" be ok - but if (as per your example) there happened to be a property called userdefined_led_name_1
in the nodes ui then you would be overwriting that... (and that may indeed be what you want...) - but just noting that ui_control may already be handled.
Testing scope grows exponentially by a factor of created configuration options count