“…not less controversy in it but more." vs "…not less but more controversy in it." Are both correct?

As for quantum theory, there was not less controversy in it, but more.

As for quantum theory, there was not less, but more, controversy.

Insertion of a comma makes the meaning of the first clearer, and preferable because it brings controversy (which is the object) to attention earlier in the reading of the sentence. I believe both are grammatically acceptable.