What Trollope does give us is an intimate look into the writing of his novels and his philosophy of work. He was a very meticulous worker, regularly writing 250 words every 15 minutes until he had two or three thousand a day. Every single day, pretty much without exception. He viewed writing as a job just as any other job you would work at. Why wait for inspiration to strike? Just pick up your pen! He also gives his opinion on every book he has written, sometimes in a brutally honest way. If he didn't think the book was any good, he will say so. But if he did think the work had merit, even if it wasn't popular, he will defend it.
He also shares his opinion of fellow writers of the day, such as Thackeray and Wilkie Collins and George Elliot, many of whom he was friends with. And he speaks to many literary issues that still affect us today, like author and critic interaction.
Anthony Trollope was an insightful man - insightful about his own work and the times in which he lived. If you're looking for a strong opinion or a behind-the-scenes look at his work, then you couldn't do any better than to read The Autobiography of Anthony Trollope.