Ha, Sansom's Cromwell is way more sympathetic than most pre-Mantel Cromwells. Here is an entertaining overview by a non-fictional Cromwell biographer, Tracy Borman, on fictional screen Cromwells before the tv version of Wolf Hall. (He makes a controversial if entertaining choice for his own favourite fictional Cromwell, btw.)

In the tv series Cromwell is definitely so far the hero who can do no wrong; in the books, the second book, Bring Up The Bodies, actually starts to show Cromwell getting darker (though still far more sympathetic than Sansom). Case in point, Cromwell's choice of lovers to accuse Anne of adultery with: "He needed guilty men, and so he picked men who were guilty, though not necessarily as charged." - He picks the men who participated in the mocking of his patron Wolsey when the Cardinal fell. (This revenge motive is entirely Mantel, btw. It's not impossible - Cromwell was emotionally attached to Wolsey, not just professionally, if his observed-by-a-hostile (Catholic)-and-hence-trustworthy-witness tears at the Cardinal's fall are anyting to go by - but what she did invent was letting all five of the accused men participate in the mocking masque ridiculing Wolsey's death, when four of them weren't even present on the occasion.) He also invents thought crime, and Mantel comes up with a great way of karmic retribution/the corruption of mind resulting from Cromwell doing what he does: after having built his case against Anne on flimsy evidence and innuendo, and seen her executed, he suddenly starts to wonder about his late,much loved and hitherto unambigously lamented wife. Was she really always faithful to him? Were his beloved daughters his daughters? At last, the paranoia he used and fueled catches up with him and he can't get the thought out of his head again, much as he wants to, those cherished memories which used to give him strength are irrevocably tainted with no one but himself to blame. BTW, I have no idea of how the tv series will dramatize this because it's all happening in Cromwell's head, and it could be utterly ooc for Mantel's Cromwell to confess these thougths to anyone.

Mind you, even the darker Cromwell of Bring Up The Bodies is still Cromwell the hero. Revenge for Wolsey may have dictated his choice of lovers to accuse Anne with, but the decision to remove Anne is made not for petty reasons but for the good of the state. The moment Cromwell decides he'll do it comes after the tournament where Henry has the fall that breaks his leg. (That injury that never heals properly; most modern biographers blame the long term result - ulcers in Henry's leg - for the weight explosion and the transformation of Henry from athletic sportsman to fat monstrosity.) When Henry has his fall, everyone panics, and before people realise Henry isn't dead, it occurs to Cromwell that if Henry dies now, without a male heir, the country will plunge into civil war. The Catholic will rally behind Mary, the reformers will be divided because some of them still will prefer Mary to baby Elizabeth, and since Anne at that point has fallen out with her uncle Norfolk on a massive scale (true), even the Boleyn/Howard faction at court is divided. And that's when Cromwell decides Anne has to go.

One major reason why I prefer Bring up the Bodies to Wolf Hall is that it contains hands down the most interesting Jane Seymour of them all. Jane Seymour usually gets cast as a bland doormat and tool of her brothers. In this novel, Jane Seymour does let herself be coached by Cromwell and her brothers, too, and is flawlessly mild yet virtuos with the king, but as it turns out, behind her carefully modest manner she's as ambitious as Anne ever was for herself. It's Jane who when the talk among her family and Cromwell is still of Anne ending up in exile or in a convent, is the first to suggest Anne needs to die.

He asks Jane, 'Would you do anything you can, to ruin Anne Boleyn?' His tone implies no reproach; he's just interested.
Jane considers: but only for a moment. 'No one need contrive at her ruin. No one is guilty of it. She ruined herself. You cannot do what Anne Boleyn did, and live to be old.'
He must study Jane, now, the expression of her downturned face. When Henry courted Anne she looked squarely at the world, her chin tilted upwards, her shallow-set eyes like pools of darkness against the glow of her skin. But one searching glance is enough for Jane, and then she casts her eyes down. (...) If Jane could veil her face completely, she would do it, and hide her calculations from the world.

So what I'm looking forward to in the last two episodes is how the screen version of this Jane will be; so far she's only been a very minor presence, but that moment in the book is a true character revelation, and I want to see it played out on screen.