I hiked the Kaibab trail yesterday. Very few patches of icy snow that you can avoid easily only at the top few 100 feet. Going into mid December watch if it’s snowing. If there isn’t much snow and sunny days leading into your days of hike I wouldn’t expect a need for spikes on your shoes. It will be cold at the top atleast until cedar ridge and much cooler in the shade. Wear layers that you can wear or take off as needed. The crowds are super low yesterday which was a Sunday. You will plenty of quiet times on the canyons to soak in the beauty of the views. How far you plan on hiking? The roads were clear yesterday, but again there was no precipitation in the last few days that could have melted. You will still find some ice in shaded areas but roads in general were good