SMAB historical fiction about Ancient Rome!

I read to my wife each night and we're planning a trip to Rome so we want to try a historical fiction about ancient Rome after we finish our current book. I loved Graves' I, Claudius, Conn Iggulden's Emperor series, Fabbri's Vespasian, Mary Beard's SPQR, and Colleen McCullough's First Man in Rome – but my wife hasn't read any books about ancient Rome and I'd rather not reread those books. She doesn't like a lot of action sequences, although military involvement is fine as long as there aren't too many detailed battle descriptions.

Here are some books that she loved (and what she liked about it): River God by Wilbur Smith (especially the royal intrigue), Kane and Abel by Jeff Archer (smooth and clear writing), Girl on the Train by Paula Hawkins (thrilling page turner).

Thank you in advance!