An expandable list of "things" in the namespace or class you're editing, similar to the tree that ODE shows when editing the same.
Actually I always have mixed sentiments wrt the way ODE handles "sections", sometimes I'd like to have a "global" list of items, regardless of the section they're in. Perhaps adding a "Global" item that had everything under it might be a suitable approach - maybe it's even worth considering that for ODE and RIDE as well.