I haven't read any of her books, but know what you mean when an author's subsequent books "go off". I really loved Maeve Binchy's first books at one time, but imo they lapsed into whimsy, also Joanna Trollope's earlier ones really good, she was great on family dynamics and then they just got awful. The crime writer Patricia Cornwall first half dozen or so, again really good, then the acronyms took over I think that's a thing sometimes with American writers, but there were so many at one time they just detracted from the plot, My husband was a big Jack Reacher fan but has said since Lee Child's brother got in on the act, they have become very mediocre.