Choose Document > Layers > Layer Extras > Active Layer from the menu and choose the One Active Layer for all Element Types option from the appearing palette.
This will set the default layer of all element types to the layer of the currently active tool (regardless of any selection). All Tool Settings dialog boxes will now use the same default Layer definition and successive elements will all be placed on that layer, regardless of type.
You can override this setting manually for selected elements.
If you wish to return to the previous layer state, choose the Individually Set Layers option. The last set of manually defined layers will be used.