The property node is extremely flexible, and you can't get into any trouble by deleting items, because they are easy to add back (see below) if necessary. Note that there is initially always only one item listed after you right-click on a control and choose Create >> Property Node.
- You can add an arbitrary number of property items by "resizing" the node with the positioning tool or by right-clicking and choosing Add Element.
- An item can be changed to any available property by right-clicking and choosing Properties >> [property]. Or, you can use the Operate tool (the pointing-finger) and left-click to get the same property list.
- You can delete a bunch of items at a time by resizing, though you are prevented from killing an already-wired item this way, and must unwire it first. Alternatively, you can always right-click and choose Remove Element with a single item.
If I were in your shoes and had created a long list of items and only needed to set three things, then I would probably either unwire-and-resize, then rewire, or I would just delete everything and create a new node from scratch with only three items.