The majority of Scheil's critiques of desired material seems to have been filled in broadly by:

Henley, Georgia, and Joshua Byron Smith, eds. A Companion to Geoffrey of Monmouth. Brill’s Companions to European History 22. Brill, 2020. http://archive.org/details/oapen-20.500.12657-42537.

Obviously this isn't an inconsequential amount of scholarship (575+ pp) to have included in Reeve's volume.

While it's nice to identify what is not in the reviewed volume, it's probably better to frame it that way rather than to seemingly blame the authors/editors for not having included such a massive amount of work. This sort of poor framing is too often seen in the academic literature. Reporting on results and work and putting it out is much more valuable in the short and long term than worrying so much about what is not there. Authors should certainly self-identify open questions for their readers and create avenues to follow them up, but they don't need to be all things to all people.

Scheel, Anne M., Mitchell R. M. J. Schijen, and Daniël Lakens. ‘An Excess of Positive Results: Comparing the Standard Psychology Literature With Registered Reports’. Advances in Methods and Practices in Psychological Science 4, no. 2 (1 April 2021): 25152459211007468. https://doi.org/10.1177/25152459211007467.

Science could learn something from this. Science is too far focused on the idealized positive outcomes that it isn't paying attention to the negative outcomes and using that to better define its outline or overall shape. We need to define a scientific opportunity cost and apply it to the negative side of research to better understand and define what we're searching for.

Of course, how can we define a new scientific method (or amend/extend it) to better take into account negative results--particularly in an age when so many results aren't even reproducible?

Booth, W., & Adam, K. (n.d.). Britain says it overcounted coronavirus death toll by 5,377. Washington Post. Retrieved August 14, 2020, from https://www.washingtonpost.com/world/britain-says-it-overcounted-coronavirus-death-toll-by-5377/2020/08/13/f6f171a6-dce0-11ea-b4f1-25b762cdbbf4_story.html

CNN, J. G., Naomi Thomas, Dana Vigue and Jacqueline Howard. (n.d.). Oxford’s Covid-19 vaccine appears safe and induces immune response, early results suggest. CNN. Retrieved August 2, 2020, from https://www.cnn.com/2020/07/20/health/oxford-covid-19-vaccine-results-cansino-pfizer-study/index.html

Blog | It’s Not Just Testing. (n.d.). The COVID Tracking Project. Retrieved June 25, 2020, from https://covidtracking.com/blog/its-not-just-testing

Importance of "spinning" data