>So the question is: "if we removed Churchill from the equation...what would the effect be on human suffering".
That was not the question: what we had was a statement that Churchill turned the war, and that without him we would have Fascist Europe standing till today - or more pointedly, as you said in another thread, all of Europe would be speaking German. So not native Fascist dictators propped up in each occupied country, but rather a pan-European Reich. Your claim is that the one thing that prevented this from being our reality today was a single man, and that man was Churchill.
I'm suggesting that no single person, even Hitler, determined the outcome of the war once set in motion. Even Hitler did not create out of whole cloth the German resentment that led to the war. He tapped into it, weaving together different aspects of public anger for his own benefit. If not Hitler, somebody else would have, and German aggression would have happened sooner or later. His tactics (ie, the SS) might have aided his speed, but it wouldn't change the inevitable outcome, which are determined more by logistics. Hitler could divert grain away from undesired natives who are just extra mouths to feed towards the frontline and influence the tide of war, but then that's exactly what Churchill did as well with the Bengal famine.
If we're talking about reduction of human suffering, then perhaps it's instructive to consider the harm that Churchill directly created in the Empire. His policies impacted the lives of hundreds of millions of people driven to the edge of destitution as a direct result of British exploitation. He may not have created the Bengal Famine, but he took a bad situation and made it infinitely much worse. Yes, I'm aware of the explanations Churchill apologists like to offer, which is a whole lot of BS. They blame the Japanese, but ignore that British policies in India had turned a net surplus producer of food grains into an importer. British India imported rice from Burma during times of shortfall, a situation created in the first place by British policies of forcing the planting of cash crops for export. A small relevant example: prior to British occupation, rice was grown all along the Gangetic plain as a winter crop, with the river deltas producing as much as three crops in a year. The British built canals to divert water away, and turned the Gangetic plains towards growing cash crops, like indigo. For anybody unfamiliar, the indigo plant is quite toxic, and poisons the land and water table for other crops. In addition, vast tracts of land were turned towards cotton farming, since Indian linen was the currency the East India Company used for international trade. When the British Crown took direct control of India, even the weaving of cotton was disallowed, diverting raw cotton to British mills. Prior to British occupation, India produced over 25% of the world's GDP, and devastating famine wasn't really a thing. British policies in India and the rest of the Empire had put hundreds of millions of people on a knife's edge of basic survival, and Churchill's policies had the ability to push millions of people one way or the other. The Bengal famine is just one example where a single choice, whatever their justification, took the life of 3 million people directly under his care that he considered "beastly with a ghastly religion". Any other PM in his position would accrue similar blame, but Churchill is not exempt because of that when the discussion is about human suffering.