How do I change the size of the text aspect on a 3d scatter plot?

If I have a marker like so:

{
       "marker": {
        "color": "rgba(179,91, 219,1)",
        "line": {
         "color": "rgba(0,0,0,0.0)"
        },
        "size": 4,
        "sizemode": "area"
       },
       "mode": "markers+text",
       "name": "S1",
       "text": "S1",
       "x": ["-7.91373451981888"],
       "y": ["0.6596385802732457"],
       "z": ["0.8892013600533066"],
       "type": "scatter3d",
       "uid": "1bb14705-f712-4bb1-9e72-6f1ff41e341a"
      }

How would I change the size of the text portion of the marker?

What about using a different font? See demo.