> When would tabbing order be desired instead of sorted by name?
When you have a relatively small number of controls and their tabbing order makes sense. It's also helpful when you drop a new control and find it without effort because it's always at the end of the list.
Another potential improvement for this is if there was a text box above the tree which could be used to filter the items shown in the tree. Essentially, it would let you search for specific controls by their labels. If the box is empty (default) the tree shows all the items. This can be very useful in VIs which have a lot of controls on the FP.