As an academic literary analysis, this suffers from the lack of clarity that is common to much academic writing, but aside from complaints about style, the analysis is novel, interesting, and at times insightful.
The connections to von Balthasar provide one of the more convincing exegesis of parts of the legendarium, drawing out a theology of beauty and transcendence expressed through the legendarium. Coutras takes Tolkien's Catholic faith and his theology more seriously than most commentators and that enables her to draw out insights that others have missed. Her exposition of his basically complementarian theology of gender reveals a gender framework that many contemporary readers will find unsatisfying as a normative matter, but that is nevertheless more complex and nuanced than many critics have given it credit for.
My only complaint, aside from my general complaint about academic style generally, is that at times Coutras seems to pull pieces of evidence from various parts of the legendarium or the letters without contextualizing them or fully explaining persuasively how they relate to the primary text she's interpreting, but this complaint is minor and doesn't detect much from the valuable insights that she draws out.