My up-and-down reaction to Memoirs of Hadrian

I'm going up and down like a yo-yo on Marguerite Yourcenar's 1951 novel, Memoirs of Hadrian. In yesterday's post I noted that after a rocky start this novel begins to get interesting in section 2 when Hadrian becomes emperor and vows to change the entire nature of Roman politics - moving from an era of expanding empire, which he believed to be unsustainable, to an era of peace: stopping the march of conquest, building strong relationships with the countries and cultures that Rome had conquered, making wise judicial decisions, etc. Unfortunately, having established his principles, Hadrian then goes on for 50 or more dense pages of text explaining he theory of governance. I'm losing sight of this work as a novel; it felt as if I were reading a philosophical tract or a book on governance. What MY seems unwilling or unable to do, now about halfway through this novel, is create any tension, conflict, or semblance of plot aside from the sequence of events in Hadrian's life. (For one thing, there is no dialogue whatsoever. For another, Hadrian is the only memorable character - although about half-way through his "boy" love, Antinous, is introduced - not that he has much personality either, but at least MY opens a new dimension in this history, an topic glossed over by most historians I would think.) I kind of cheated and looked ahead at the two appendices: MY's account of her research and some of her notes during the composition of the novel. I learned from these appendices that she did an enormous amount of scholarly research, involving many primary sources - enough to qualify this novel as serious scholarship (though she notes that she made some changes to historical fact in the interest of narrative). Also learned that she began this project in the 1920s (when she was about 25), dropped it and picked it up again at several points - the story of Hadrian had always fascinated her. It would be good if she could say precisely why, or what specific relevance Hardian's governance had for life in postwar Europe. I will read further in the novel today, and maybe the up-and-down process will continue, but I fear that I'm losing the thread here and may not want to pursue the narrative, such as it is, to the end.