If you observe a body of literature and you can formulate from it another research, this could be a twigging of a research into new research domains, not necessarily a review paper.
In my process of writing come additional remarks in the text nearly always. So the text and references get more manifoldly but perhaps also overcharged. There are several possibilities. To change the structure by adding one ore ore chapters, or to develop a long and a short version of your text. Finally you may discover a variation of the initial leading question of your research topic. Such processes extend the whole article or book, but in my experience it is no disadvantage
I disagree with whom said that " the formulation of a paper from literature make review article not research article"; even when you want write a research paper you should read and do a literature search to define the results, the strengths and the weaknesses of other papers.