Why would you say this is a weird design?

My combo class is loaded from a lookup table. If I didnt see an item that applied to the record, I would see the "Edit ... Type" bar and it launches a dialog and it becomes blindingly obvious what to do next.

I agree the button is a decent idea, however with the button, I would
have to have the tooltip text set, not a big deal either, but the combo
is already open, whereas with the button, I have to try it once the
first time just to see what it does. Also, with the button idea, I would
now have to have a button class to go along with the list, whereas the
list automagically sets itself up from a table.

I dunno; six one way - half dozen the other I guess.