Yes, maybe something along "built specifications...built control". This would make a plain "*.ctl" file that can e.g. be put in the user palette or distributed, but retains all functionality of the Xcontrol.
(examples could be an xy-chart (with settable history size) or a fake radio button control that allows up to two items selected, or even some fancy airplane control, such as an artificial horizon).
Still, I see some problems, e.g. it is probably not easily possible to support "advanced...customize" or even resizing.