I have a pet theory that it’s difficult for her to convince the far right wing of the court to let her write the majority opinion, and that’s part of what is fueling these uncharacteristic or “independent” moments.
When the Court rules to the center, I think Roberts likes to take it himself or let a liberal Justice write it so it looks like the court is balanced and unified or something.
Roberts has lost control of his court and is desperately trying to make it appear legitimate.
She doesn’t have to convince the “far right wing”. As long as CJ Roberts (not generally regarded as in any “wing”) is in the majority, he can assign the opinion to her.
I am pretty sure the Chief Justice chooses who writes the opinion when he (or, one day, she) is in the majority, and if that's right, then Roberts is the only one she would have to convince