" I am still struggling with what kind of a man he is? Is he good, bad, manipulative?"
This is the core of history, isn't it? How can we ever tell? People are such complex entities.
Generally speaking, history has not been kind to Cromwell: the overarching view seems to cast him as the scheming toad portrayed by the Holbein painting. At least in part, this has its roots in the resentment of so many of the court at the time: mired in the ideology of a divinely-ordained hierarchy, there was an atmosphere of envy and mistrust amongst the nobles, who felt quite aggrieved at the elevation of a lowly blacksmith's son to such an exhalted position of power. Add to that the turmoil of the Reformation, and Cromwell's overseeing of the destruction of monastic life, plus the various executions and machinations of the State, and it's not hard to see how posterity records Cromwell as a controversial and sometimes hated figure.
Hilary Mantel has gone back to the source material and reimagined him in a more sympathetic light. She focuses on his proven loyalty to his masters, his extreme talent, his ability to divine what people want and 'make it so' in a court which required astonishing cunning and nimble diplomacy just to survive. We know from the records that he was generous to his friends, and kind to the poor, and there is evidence that he valued education for his daughters as much as his son.
I'm not sure it's ever possible to say what the "truth" is about a person, but I certainly think that it is more interesting to see that a historical figure may have more complex characteristics and motivations than they might have been credited with.