The more general material is wide-ranging, covering or at least touching on the life of the Buddha, the history of Buddhism in India, the 19th century invention of "Buddhism" by Orientalists such as de Körös, Buddhism in the West, Ambedkarite neo-Buddhism, and so forth. Here again there are diversions — to Japanese nationalism, Adam Smith and David Hume and Western individualism, Gandhi and the modern history of India, and much more.
Mishra's summaries of history and analyses of religion are easy to read and mostly unobjectionable, but he is clearly not a historian by training and the seams in the secondary sources he has stitched together are sometimes visible. And in a few places his generalisations go completely awry, with nonsense such as "the early Indians, faced with problems of subsistence, couldn't but be materialists".
Mishra is primarily interested in the philosophical ideas underpinning Buddhism and in how they can be related to Western philosophy. There's almost nothing about Buddhism in Southeast or East Asia, or about Buddhist ritual and practice. And Mishra's view of Buddhism seems somewhat idealised, often contrasted with a fundamentalist Hinduism he finds uncongenial.
I found the more personal material in An End to Suffering the most appealing; for the history I might have preferred more specialised works. Mishra's approach falls nicely, however, between academic studies and "pop" presentations pitched to New Age preconceptions. I recommend An End to Suffering to anyone curious about Buddhism who is familiar with or interested in Nietzsche, Proust and Plato — it should be a hit with Mishra's regular audience at the New York Review of Books.