Uncle Tom's Cabin brought home nothing but a pantsload of cheap, emotive propaganda. Stowe was committing propaganda, she wasn't trying to write a reasoned description of slavery.
If she relied on Frederick Douglass, by the way, for her descriptions of slave life, she'd have done herself and her readers a disservice, inasmuch as Douglass admitted, later in his life, to having amped up his earlier descriptions of the injustices of slave life.
The real problem with slavery as an institution was that its intimate identification with property rights made it very difficult to take up as a policy matter without exciting the reasonable fear that an attack on all property rights was on offer, as well as a sectional political attack.
This was a reasonable apprehension, given the Whigs' and Federalists' demonstrated enthusiasm for the politics of "tax tax, spend spend"; and it was the Republican Party that introduced the first income tax. This was in addition to the punitive property taxes they enacted specifically for the purpose of expropriating Confederates' homes and farms.
Actually the "real" problem with slavery was not that to remove it was an attack on property rights. The real problem was that defining humans as property contradicted everything the American revolution stood for.
Your inability to comprehend this simple point allows you to blather endlessly on defending the Slavers.