'pivotal theme' is correct and usable in written English.
It's used to describe a key, important, or central idea or topic that forms the foundation of a work of literature or other creative work. For example, "The pivotal theme of the novel is family loyalty."
Given that Waller-Bridge's guilt over the death of her best friend, Boo, has been such a pivotal theme through both series, there was an odd lack of explicit resolution.
In announcing his proposals, Mr. Clinton returned to a pivotal theme of his career, an issue on which he won the presidency in 1992 and then ran aground two years later.
But Obama's embrace of what he calls "middle-class economics" – as opposed to the trickle-down economics of the Republicans – is likely to ensure that inequality remains a pivotal theme of the 2016 presidential campaign.
A third pivotal theme pertains to accessible technology and communications during disaster.
A second pivotal theme regards the emphasis placed on inclusivity of disaster preparedness, response, and mitigation activities.
A final pivotal theme pertains to the essential role of individuals with disabilities and disability advocacy organizations as stakeholders and collaborators in emergency planning and recovery.
Enhancing vehicles performance is one of the pivotal themes that has received considerable attention recently.
"We touched on some of the more pivotal themes and ideas, the structure of the storyline, the characters, the Upside-Down, and the entity monster," added Stein.
Several pivotal themes, each with philosophical origins in disability theory and research, permeated both the SFDRR and the WCDRR meeting itself.
The duo wanted to expose the novels' pivotal themes, particularly misogyny.
Race and injustice will be pivotal themes in the lead-up to South Carolina's Republican primary on February 20 and the Democratic primary on February 27.
